Changes

OBS: support building debian trixie (13) pkgs

Translate "debian:13" to "debian:trixie", as for some reason no docker
tag is getting pushed for "debian:13". With this we can keep using the
usual short naming scheme in pipeline_binpkgs lines in
gerrit-verifications.yml (see next patch).

Change-Id: I1377af7f74f074ed6e28e07dee82360d024edd05