deps: Add python3-repomd to the list of deps
This is needed for the latest swh-lister > v4.3.
I need the latest swh.lister for gitea/gogs listers in production. The build is stuck without that new debian package (for now). I have the necessary changes ready (at least for unstable in that repository). This would allow jenkins to let it build and push the debian package to our debian repository.
Finally unstucking the lister build.
Related to https://gitlab.softwareheritage.org/infra/sysadm-environment/-/issues/4684 Related to https://gitlab.softwareheritage.org/infra/sysadm-environment/-/issues/4686
Test Plan
tox is happy
Migrated from D8990 (view on Phabricator)