[Group] Update write client for groups

[jepenven-silabs]

Problem

partial fix of #11078

As discussed with @bzbarsky-apple issue 11078 will be fixed with a multiple of small PR. This will (hopefully) speed up the review process and shouldn't break anything since there's nothing to break regarding group communication.

Change overview

Update write client for group session to allow group attribute write.

Testing

A Unit test was added, however it will need an update once #11078 is complete.

[github-actions]

PR #11601: Size comparison from e6dab37 to 914c376

Increases (3 builds for linux)

platform	target	config	section	e6dab37	914c376	change	% change
linux	chip-tool	debug	(read only)	4995029	4995173	144	0.0
			.text	4481717	4481861	144	0.0
	ota-requestor-app	debug	(read only)	1344281	1344425	144	0.0
			.text	1121250	1121394	144	0.0
	tv-app	debug	(read only)	1842281	1842441	160	0.0
			.text	1541906	1542066	160	0.0

Full report (38 builds for efr32, esp32, k32w, linux, mbed, nrfconnect, p6, qpg, telink)

platform	target	config	section	e6dab37	914c376	change	% change
efr32	lighting-app	BRD4161A	(read only)	742904	742904	0	0.0
			(read/write)	116268	116268	0	0.0
			.bss	114484	114484	0	0.0
			.data	1784	1784	0	0.0
			.text	742896	742896	0	0.0
		BRD4161A+rpc	(read only)	730440	730440	0	0.0
			(read/write)	132892	132892	0	0.0
			.bss	130988	130988	0	0.0
			.data	1900	1900	0	0.0
			.text	730432	730432	0	0.0
	lock-app	BRD4161A	(read only)	722192	722192	0	0.0
			(read/write)	114084	114084	0	0.0
			.bss	112340	112340	0	0.0
			.data	1744	1744	0	0.0
			.text	722184	722184	0	0.0
	window-app	BRD4161A	(read only)	723088	723088	0	0.0
			(read/write)	114412	114412	0	0.0
			.bss	112660	112660	0	0.0
			.data	1748	1748	0	0.0
			.text	723080	723080	0	0.0
esp32	all-clusters-app	c3devkit	(read only)	880694	880694	0	0.0
			(read/write)	1306536	1306536	0	0.0
			.dram0.bss	58464	58464	0	0.0
			.dram0.data	16472	16472	0	0.0
			.flash.rodata	198360	198360	0	0.0
			.flash.text	880694	880694	0	0.0
			.iram0.text	57526	57526	0	0.0
		m5stack	(read only)	911867	911867	0	0.0
			(read/write)	423864	423864	0	0.0
			.dram0.bss	60968	60968	0	0.0
			.dram0.data	32108	32108	0	0.0
			.flash.rodata	204624	204624	0	0.0
			.flash.text	911867	911867	0	0.0
			.iram0.text	125115	125115	0	0.0
k32w	lighting-app	k32w061+se05x+release	(read/write)	699648	699648	0	0.0
			.bss	77996	77996	0	0.0
			.data	1912	1912	0	0.0
			.text	613940	613940	0	0.0
	lock-app	k32w061+debug	(read/write)	592360	592360	0	0.0
			.bss	68524	68524	0	0.0
			.data	1880	1880	0	0.0
			.text	516156	516156	0	0.0
	shell	k32w061+debug	(read/write)	658016	658016	0	0.0
			.bss	79324	79324	0	0.0
			.data	1848	1848	0	0.0
			.text	571044	571044	0	0.0
linux	all-clusters-app	debug	(read only)	1710601	1710601	0	0.0
			(read/write)	126528	126528	0	0.0
			.bss	57872	57872	0	0.0
			.data	1042	1042	0	0.0
			.data.rel.ro	62352	62352	0	0.0
			.dynamic	592	592	0	0.0
			.got	4088	4088	0	0.0
			.init	27	27	0	0.0
			.init_array	552	552	0	0.0
			.rodata	139765	139765	0	0.0
			.text	1437346	1437346	0	0.0
	bridge-app	debug+rpc	(read only)	1298253	1298253	0	0.0
			(read/write)	77072	77072	0	0.0
			.bss	42768	42768	0	0.0
			.data	1568	1568	0	0.0
			.data.rel.ro	27760	27760	0	0.0
			.dynamic	592	592	0	0.0
			.got	3952	3952	0	0.0
			.init	27	27	0	0.0
			.init_array	408	408	0	0.0
			.rodata	111540	111540	0	0.0
			.text	1090821	1090821	0	0.0
	chip-tool	debug	(read only)	4995029	4995173	144	0.0
			(read/write)	134760	134760	0	0.0
			.bss	25840	25840	0	0.0
			.data	2256	2256	0	0.0
			.data.rel.ro	101232	101232	0	0.0
			.dynamic	592	592	0	0.0
			.got	4368	4368	0	0.0
			.init	27	27	0	0.0
			.init_array	432	432	0	0.0
			.rodata	242064	242064	0	0.0
			.text	4481717	4481861	144	0.0
	lighting-app	debug+rpc	(read only)	1557945	1557945	0	0.0
			(read/write)	110088	110088	0	0.0
			.bss	48432	48432	0	0.0
			.data	1202	1202	0	0.0
			.data.rel.ro	55168	55168	0	0.0
			.dynamic	608	608	0	0.0
			.got	4112	4112	0	0.0
			.init	27	27	0	0.0
			.init_array	528	528	0	0.0
			.rodata	128977	128977	0	0.0
			.text	1295410	1295410	0	0.0
	ota-provider-app	debug	(read only)	1259721	1259721	0	0.0
			(read/write)	75336	75336	0	0.0
			.bss	44864	44864	0	0.0
			.data	752	752	0	0.0
			.data.rel.ro	24616	24616	0	0.0
			.dynamic	592	592	0	0.0
			.got	4016	4016	0	0.0
			.init	27	27	0	0.0
			.init_array	448	448	0	0.0
			.rodata	113216	113216	0	0.0
			.text	1050258	1050258	0	0.0
	ota-requestor-app	debug	(read only)	1344281	1344425	144	0.0
			(read/write)	79104	79104	0	0.0
			.bss	47328	47328	0	0.0
			.data	816	816	0	0.0
			.data.rel.ro	25880	25880	0	0.0
			.dynamic	592	592	0	0.0
			.got	3992	3992	0	0.0
			.init	27	27	0	0.0
			.init_array	472	472	0	0.0
			.rodata	124232	124232	0	0.0
			.text	1121250	1121394	144	0.0
	shell	debug	(read only)	789065	789065	0	0.0
			(read/write)	65480	65480	0	0.0
			.bss	23912	23912	0	0.0
			.data	242	242	0	0.0
			.data.rel.ro	36816	36816	0	0.0
			.dynamic	592	592	0	0.0
			.got	3528	3528	0	0.0
			.init	27	27	0	0.0
			.init_array	344	344	0	0.0
			.rodata	78191	78191	0	0.0
			.text	609362	609362	0	0.0
	tv-app	debug	(read only)	1842281	1842441	160	0.0
			(read/write)	407936	407936	0	0.0
			.bss	340112	340112	0	0.0
			.data	2736	2736	0	0.0
			.data.rel.ro	59448	59448	0	0.0
			.dynamic	592	592	0	0.0
			.got	4408	4408	0	0.0
			.init	27	27	0	0.0
			.init_array	616	616	0	0.0
			.rodata	156456	156456	0	0.0
			.text	1541906	1542066	160	0.0
mbed	all-clusters-app	CY8CPROTO_062_4343W+release	(read only)	6224	6224	0	0.0
			(read/write)	2290856	2290856	0	0.0
			.bss	179436	179436	0	0.0
			.data	5232	5232	0	0.0
			.heap	851776	851776	0	0.0
			.text	1253456	1253456	0	0.0
	lighting-app	CY8CPROTO_062_4343W+release	(read only)	6224	6224	0	0.0
			(read/write)	2270952	2270952	0	0.0
			.bss	172492	172492	0	0.0
			.data	5584	5584	0	0.0
			.heap	858368	858368	0	0.0
			.text	1233552	1233552	0	0.0
	lock-app	CY8CPROTO_062_4343W+release	(read only)	6224	6224	0	0.0
			(read/write)	2248672	2248672	0	0.0
			.bss	171388	171388	0	0.0
			.data	5568	5568	0	0.0
			.heap	859488	859488	0	0.0
			.text	1211272	1211272	0	0.0
	pigweed-app	CY8CPROTO_062_4343W+release	(read only)	6224	6224	0	0.0
			(read/write)	1139744	1139744	0	0.0
			.bss	11752	11752	0	0.0
			.data	4368	4368	0	0.0
			.heap	1020328	1020328	0	0.0
			.text	103128	103128	0	0.0
	shell	CY8CPROTO_062_4343W+release	(read only)	6224	6224	0	0.0
			(read/write)	2048864	2048864	0	0.0
			.bss	156456	156456	0	0.0
			.data	4976	4976	0	0.0
			.heap	875016	875016	0	0.0
			.text	1011464	1011464	0	0.0
nrfconnect	lighting-app	nrf52840dk_nrf52840	(read/write)	862155	862155	0	0.0
			bss	111460	111460	0	0.0
			rodata	96924	96924	0	0.0
			text	578128	578128	0	0.0
		nrf52840dk_nrf52840+rpc	(read/write)	824503	824503	0	0.0
			bss	107812	107812	0	0.0
			rodata	88104	88104	0	0.0
			text	552276	552276	0	0.0
		nrf5340dk_nrf5340_cpuapp	(read/write)	787162	787162	0	0.0
			bss	112832	112832	0	0.0
			rodata	92180	92180	0	0.0
			text	507600	507600	0	0.0
	lock-app	nrf52840dk_nrf52840	(read/write)	838831	838831	0	0.0
			bss	110492	110492	0	0.0
			rodata	93296	93296	0	0.0
			text	559612	559612	0	0.0
		nrf5340dk_nrf5340_cpuapp	(read/write)	764142	764142	0	0.0
			bss	111904	111904	0	0.0
			rodata	88600	88600	0	0.0
			text	489176	489176	0	0.0
	pigweed-app	nrf52840dk_nrf52840	(read/write)	497327	497327	0	0.0
			bss	51824	51824	0	0.0
			rodata	45780	45780	0	0.0
			text	339436	339436	0	0.0
	pump-app	nrf52840dk_nrf52840	(read/write)	844955	844955	0	0.0
			bss	110632	110632	0	0.0
			rodata	95004	95004	0	0.0
			text	563772	563772	0	0.0
	pump-controller-app	nrf52840dk_nrf52840	(read/write)	838699	838699	0	0.0
			bss	110528	110528	0	0.0
			rodata	93292	93292	0	0.0
			text	559348	559348	0	0.0
	shell	nrf52840dk_nrf52840	(read/write)	776431	776431	0	0.0
			bss	109280	109280	0	0.0
			rodata	72564	72564	0	0.0
			text	520004	520004	0	0.0
		nrf5340dk_nrf5340_cpuapp	(read/write)	691482	691482	0	0.0
			bss	110264	110264	0	0.0
			rodata	67204	67204	0	0.0
			text	440612	440612	0	0.0
p6	all-clusters-app	default	(read/write)	2299528	2299528	0	0.0
			.bss	112448	112448	0	0.0
			.data	2536	2536	0	0.0
			.heap	918360	918360	0	0.0
			.text	1257792	1257792	0	0.0
	lock-app	default	(read/write)	2212184	2212184	0	0.0
			.bss	101256	101256	0	0.0
			.data	2408	2408	0	0.0
			.heap	929680	929680	0	0.0
			.text	1170448	1170448	0	0.0
qpg	lighting-app	qpg6100+debug	(read only)	490776	490776	0	0.0
			(read/write)	114140	114140	0	0.0
			.bss	51152	51152	0	0.0
			.data	1012	1012	0	0.0
			.text	485456	485456	0	0.0
	lock-app	qpg6100+debug	(read only)	466988	466988	0	0.0
			(read/write)	114144	114144	0	0.0
			.bss	50096	50096	0	0.0
			.data	968	968	0	0.0
			.text	461668	461668	0	0.0
	persistent-storage-app	qpg6100+debug	(read only)	153400	153400	0	0.0
			(read/write)	114140	114140	0	0.0
			.bss	19616	19616	0	0.0
			.data	364	364	0	0.0
			.text	148080	148080	0	0.0
telink	lighting-app	tlsr9518adk80d	(read/write)	663750	663750	0	0.0
			bss	69272	69272	0	0.0
			noinit	33216	33216	0	0.0
			text	458596	458596	0	0.0