Release 1.12.5

• Fixed a case where temrporary data was sometimes left in
  /var/lib/flatpak/appstream, and we now detect such leftover data and
  remove it.
• Fix regressions in flatpak history since 1.9.1
  • Don't display the appstream branch used internally
  • Don't display temporary repositories used internally
  • Warn instead of failing if other non-app, non-runtime refs are found
  • Don't set up an unnecessary polkit agent for flatpak history
  • Add test coverage
• Don't propagate GStreamer-related environment variables into sandbox
• Fix a typo in an error message
• Fix incorrect year in NEWS for 1.12.4 release
• Translation update: pl

$ sha256sum flatpak-1.12.5.tar.xz 
1cb4a0b0b0c1bdffe644011ee8d17e437b4917c21d4384ec111b3f328206166c  flatpak-1.12.5.tar.xz