Munin multi-node fixes

[jb3]

• Configure firewalld with new wireguard zone
• Configure new firewalld rule to allow munin-node in wireguard zone
• Add scraping config to munin master against all ansible hosts
• Update munin-node config to allow scraping from any configured wireguard host

[jb3]

/merge

[pydis-ff-bot[bot]]

:white_check_mark: Successfully fast-forwarded commits from python-discord:jb3/munin/multi-node-fixes onto main

[github-actions[bot]]

Thanks!