[gnome-builder] (22 commits) Non-fast-forward update to branch gitlabci

[Jordan Petridis <jpetridis src gnome org>]

The branch 'gitlabci' 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:

  73408b5... gitlabci: Improve caching
  8376626... gitlabci: Disable ccache

Commits added to the branch:

  766eb87... gitlabci: Disable ccache. (*)
  2d33929... flatpak: fix wrong cwd when running a command through "flat (*)
  e617b0a... flatpak: add strv_empty() helper to avoid walking strv (*)
  3e01668... Fix meson targets introspection (*)
  03ecd89... Fix meson tests introspection (*)
  e609c15... meson: avoid second call to get builddir (*)
  31669ab... flatpak: use meson to build devhelp (*)
  d03ce81... sysroot: add a new plugin allowing to specify the sysroot (*)
  9d77e36... sysroot: align with project code-style (*)
  89198fc... sysroot: rename IdeSysroot* to GbpSysroot (*)
  23b3fc1... sysroot: add documentation to the public methods (*)
  92b79a8... doc: add sysroot configuration to the documentation (*)
  dc16924... sysroot: fix tiny code style issue (*)
  afcb10f... sysroot: try to guess the pkgconfig paths and always show t (*)
  5606fde... sysroot: fix ownership transfer of path (*)
  360710b... sysroot: fixup warnings and messages (*)
  db149c1... sysroot: code style clean up (*)
  40f44d7... sysroot: improve styling of preferences popover (*)
  520cf0f... doc: improve sysroot documentation (*)
  345d9fc... sysroot: use pan-down-symbolic (*)
  cc3a135... Update POTFILES.in (*)
  3496d37... gitlabci: Change the git submodule initialization strategy

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