The unversioned python packages are not shipped in Bullseye/sid anymore, and even old versions are not installable anymore. This makes vmdebootstrap and some dependencies of our test suite (#15349 (closed), #17031 (closed)) uninstallable.
So, I've uploaded to our custom APT repo some fake unversioned python packages, which allow installing a Tails build & test environment on Bullseye/sid.
The control files added by this commit are used to generate these fake packages with equivs-build.
While I'm at it, I'm documenting how to install vmdebootstrap on Bullseye and newer.
Closes #17858 (closed)