Bug#1099164: pygobject: Don't include 3.51 with trixie

[Jeremy Bícha]

Source: pygobject
Version: 3.51.0-1
Severity: serious
X-Debbugs-CC: alessandro.astone at canonical.com, seb128 at ubuntu.com

The new pygobject series is a major update and I don't believe we have
time on the team to fix its issues now. Therefore, we should stick
with pygobject 3.50.x for trixie.

Several autopkgtests for reverse depends are failing. And most things
that use pygobject don't have autopkgtests:
https://release.debian.org/britney/pseudo-excuses-experimental.html#pygobject

Here's an upstream issue for an affected app:
https://gitlab.gnome.org/GNOME/gnome-music/-/issues/641

Thank you,
Jeremy Bícha