[Suggestion] Allow custom upgrade commands

[Pyro57000]

Is your feature request related to a problem? Please describe.
I use distrobox to automatically create new containers for each pentest engagement I work on keeping the client files and data separate from each other. I primarily use arch linux for these boxes, and most of my tools can be upgraded via pacman, but there's a handful that rely on the AUR. I would like to replace pacman in this case with yay to upgrade both pacman and the AUR and also add the pipx upgrade command to upgrade all the pipx packages as well.

Describe the solution you'd like
I would like the ability to set a custom upgrade command for containers so that when I run distrobox-upgrade all it'll actually upgrade all of my packages for all of my distroboxes.

Describe alternatives you've considered
Manually entering each distrobox and running my upgrade commands. This is what I currently do, but I feel like it defeats the purpose of the distrobox upgrade command and is not very convenient

[boredsquirrel]

Silly recommendation but

echo "alias pacman=yay" >> ~/.bashrc

Is a good workaround. If you always use a different package manager you might just alias it.

[Pyro57000]

That's true, I can't believe I didn't think consider that. Still an official way to adjust the config of distrobox to do something similar would be nice, especially if you wanted to integrate other package managers into the update process like for example pipx, rustup, flatpak, nix, etc. having the ability to set the upgrade command to either a custom script or bash one liner would be great.