Test BGP peer prefix count

[bytinbit]

Test how many Prefixes a BGP Peer announces. Answer is a range, test succeeds if the result is within that range.

the command that returns the prefixes is show bgp neighbor details, however, NUTS' BGP neighbors test bundle currently uses show bgp neighbor. If we implement the prefixes, we probably must adjust the existing BGP neighbors test bundle.

Napalm-Doku: [https://github.com/napalm-automation/napalm/blob/develop/napalm/base/base.py#L771]

There's no urgency to implement the test.