doc: Replace typo BANDIWDTH to BANDWIDTH (backport #9399)

[mergify]

This is an automatic backport of pull request #9399 done by Mergify.

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[LabN-CI]

💚 Basic BGPD CI results: SUCCESS, 0 tests failed

Results table

_	_
Result	SUCCESS git merge/9406 803bff9
Date	08/16/2021
Start	04:55:23
Finish	05:21:42
Run-Time	26:19
Total	1813
Pass	1813
Fail	0
Valgrind-Errors	0
Valgrind-Loss	0
Details	vncregress-2021-08-16-04:55:23.txt
Log	autoscript-2021-08-16-04:56:36.log.bz2
Memory	517 497 413

For details, please contact louberger

[NetDEF-CI]

Continuous Integration Result: SUCCESSFUL

Congratulations, this patch passed basic tests

Tested-by: NetDEF / OpenSourceRouting.org CI System

CI System Testrun URL: https://ci1.netdef.org/browse/FRR-FRRPULLREQ-21083/

This is a comment from an automated CI system.
For questions and feedback in regards to this CI system, please feel free to email
Martin Winter - mwinter (at) opensourcerouting.org.