[pitivi] (14 commits) Created branch clipprops

[Alexandru Băluț <alexbalut src gnome org>]

The branch 'clipprops' was created.

Summary of new commits:

  0987ea9... tests: Move the utility logic in a single class
  4488180... clipproperties: Fix single-clip selection restoring
  c863fe7... timeline: Restore the selection only if all the clips have 
  f06a158... clipproperties: Fix effects expander visibility
  8e7da9f... pipeline: Debug what async operation was being executed
  cb3d53b... docs: Fix debug instructions
  19cea89... render: Quality widget for supported encoders
  4856156... render: Select the YouTube preset initially
  0e401f9... render: Make sure to revert boolean field
  e428361... profile: Rename variables to use the Gstreamer terminology
  45d0435... render: Show the matching profile
  e6bd765... tests: Cleanup
  0c6502e... docs: Update GSoC pages
  39b9bf8... flatpak: Force GStreamer 1.18 so we release