At the moment, VyOS requires an older version of bash-completion for the CLI scripts to work. We currently pull it from the Debian Buster repository. The problem with that approach is that it creates a potential for other packages accidentally getting pulled from that repo, and the repo itself will eventually stop being readily usable, since Buster already reached EOL.

That package is a bunch of shell scripts and thus doesn't have a complicated build procedure or dependencies, so we should just build it from source.