We're now using the built-in deb822_repository module to handle
Debian package repositories. We no longer need individual yml files
per repo and instead perform just one loop call of the
deb822_repository module. We also update repo content to Proxmox VE 9
and Debian 13.
We're doing this because at the end of the Proxmox VE 8 lifecycle in
August of 2025 the pve8to9 migration check script indicated if would
be potentially beneficial to install the amd64-microcode package for
microcode updates to our processor.
We agree which is why we need the non-free-firmware component to be
able to install amd64-microcode.