Enabling BLE advertising start/stop command in shell application

[tima-q]

Problem

BLE commands (btp) in shell application are currently stubs.
Not all commands can be executed on a CHIP device side either.
The advertising start/stop can be enabled for a CHIP BLE peripheral.

Summary of Changes

Advertising command enabled using the ConnectivityMgr()
Scanning and setting up a connection has no API within ConnectivityMgr()

[github-actions]

Size increase report for "nrfconnect-example-build" from 69dcdb5

File	Section	File	VM
chip-shell.elf	text	80	80
chip-shell.elf	rodata	64	68

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-lighting.elf and ./pull_artifact/chip-lighting.elf:

sections,vmsize,filesize

Comparing ./master_artifact/chip-lock.elf and ./pull_artifact/chip-lock.elf:

sections,vmsize,filesize

Comparing ./master_artifact/chip-shell.elf and ./pull_artifact/chip-shell.elf:

sections,vmsize,filesize
.debug_info,0,11908
.debug_line,0,453
.debug_abbrev,0,355
.strtab,0,255
.symtab,0,96
text,80,80
rodata,68,64
.debug_loc,0,64
.debug_ranges,0,48
.debug_frame,0,4
.shstrtab,0,1