More package managers in PMM

[TheOddCell]

meta-package-manager is a useful package manager for package managers.
you might think this is the same as PMM, a bedrock utility, but it updates other package managers such as:

• pip&pipx
• flatpak
• fwupd
• yay
• deb-get
• etc.

that are not system ones.
suggestion: add them to PMM. MPM is broken (at least for me) on bedrock, as it only does one system package manager (apt for me) and doesn't attempt managers like yay.

EDIT: added deb-get

[TheOddCell]

I found line 546 in /bedrock/etc/bedrock.conf, but it doesn't do everything