[pygobject] (2 commits) Non-fast-forward update to branch wip/jfelder/gtk4-sort-list-model

[Jean Felder <jfelder src gnome org>]

The branch 'wip/jfelder/gtk4-sort-list-model' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  a9a116f... gtk: Add override for Gtk.CustomSorter.set_sort_func

Commits added to the branch:

  7df0016... examples/demo: Use require_version to force gtk3 (*)
  f84197e... gtk: Add override for Gtk.CustomSorter.set_sort_func

(*) This commit already existed in another branch; no separate mail sent