feat: add ssh_backup option with default true

[skwde]

No description provided.

[Jakuje]

Code-wise looks good. Would be great if we could have some test coverage for this option. You can get some inspiration from the sshd role, which has sshd_backup option and test for that:

https://github.com/willshersystems/ansible-sshd/blob/master/tests/tests_backup.yml

[richm]

ping - also requires rebase

[skwde]

I did the rebase + added the adjusted backup tests (as in ansible-sshd). I however cannot properly test because I don't get tox-lsr running on my machine.

I would thus appreciate if somebody else could fix the remaining issues.

[richm]

[citest]

[richm]

lgtm, except for the minor ansible-lint issues, and the Ubuntu tests

[Jakuje]

I squashed the commits and added fixes/tests improvements to make the Ubuntu checks working in my branch where the CI now passes:
https://github.com/Jakuje/ssh/commits/add_ssh_backup_option
Feel free to pull the test fix commits or I can create a new PR.

[Jakuje]

Please, rebase instead of merging to have nicer git history. Now the CI is green we should be good to go.

[skwde]

@Jakuje it should be fine now.

[Jakuje]

Thank you! Asking also @richm for review/merge as some of the test cleanup commits was from me.