[gtk] (3 commits) Non-fast-forward update to branch wip/otte/x11-testsuite

[Benjamin Otte <otte src gnome org>]

The branch 'wip/otte/x11-testsuite' 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:

  935bca4... testsuite: Split X11 testsuite
  4ff837b... CI: Use mutter for the x11-full testsuite run

Commits added to the branch:

  4f9bd99... Add mutter and lcms2-devel to the Fedora image
  31d052a... testsuite: Split X11 testsuite
  9b2f136... CI: Use mutter for the x11-full testsuite run