Fixed for 1.3+ along with test verifications

PR: https://github.com/vyos/vyos-1x/pull/4240

I was looking into this again today. As I mentioned in the pull request, there is an issue with the draft PR. What happens is that the current config is retrieved using the command show configuration commands instead of show configuration. The output does not contain any less specific config paths, as they would be useless in configuring a system. However, when determining what to delete, this information is essential.

Seems the following fixed it in the code. At the very least it didn't error anymore. I'll happily try to make a merge request for it but I've never done that on a project of this scale before so I'd like some guidance.

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Clients cannot connect with empty crl file

# vyos@r14:~$ sudo cat /run/openvpn/vtun10_crl.pem 
# vyos@r14:~$

Blackbox exporter requires a config file for modules that should be used (for example ping over IPv4 or IPv6, DNS for A or AAAA).

This feature is missing documentation: https://docs.vyos.io/en/latest/configuration/service/monitoring.html

https://github.com/vyos/vyos-1x/pull/4238
https://github.com/vyos/libnss-tacplus/pull/1

The exclude_users string can not have an infinite length.

https://github.com/vyos/vyos-1x/pull/4227
https://github.com/vyos/vyos-build/pull/853

Some thoughts.

Based on your suggestion, I submitted a PR to accept the traffic for the PPPoE session. However,I'm not sure how to accept these STP traffic , so the STP was not included.

The fix is now a part of https://github.com/vyos/vyos.vyos/pull/367