[gupnp] (8 commits) Non-fast-forward update to branch wip/24

[Jens Georg <jensgeorg src gnome org>]

The branch 'wip/24' 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:

  1a00dce... service: Validate host header
  bf6f47e... Tests: Add test for host header validation

Commits added to the branch:

  8a34954... service-action: Protect against unsent message use (*)
  0f59d90... service-action: Do not leak message if never sent (*)
  35bba25... context: Small code cleanup (*)
  e7f9837... service-proxy: Do not keep action alive on error (*)
  bd58180... CI: Enable CI build (*)
  2593943... ci: exclude subprojects from tests (*)
  babad0f... service: Validate host header
  354f3e2... Tests: Add test for host header validation

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