Do a few things:
- add a build for Debian trixie (as discussed in #4182);
- add a build for Ubuntu 24.04;
- rename the build definitions to match the build names;
- update the artifact uploads to use a non-deprecated version of the
action, and name the artifact appropriately;
- remove a stale workflow file.
Signed-off-by: Michael Keller <github@ike.ch>
