[gtk] (9 commits) Non-fast-forward update to branch matthiasc/for-master

[Matthias Clasen <matthiasc src gnome org>]

The branch 'matthiasc/for-master' 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:

  0401e55... Fix the build with clang

Commits added to the branch:

  d3443d6... ci: Use the timeout multiplier from the environment (*)
  70e4dab... ci: Increase the timeout multiplier (*)
  b3dc517... ci: Use lsan again (*)
  333b013... Increase the default timeout for slow tests (*)
  ad04da8... Add the filtermodel-exhaustive test to the slow suite (*)
  0578422... build: Restructure the tests to use dictionaries (*)
  6aafb81... Merge branch 'ci-tweaks' into 'master' (*)
  7c8cd23... Merge branch 'ebassi/ci-timeout' into 'master' (*)
  55217e2... Fix the build with clang

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