installed-media: Load and extract .ova async

Since commits 4aad2ce and 5306e74 in libvof-glib, we are able to
perform asynchronously both the loading of ova files and the
extraction of disks.
5 jobs for wip/kalev/ovf-support in 49 minutes and 32 seconds (queued for 3 seconds)
Status Name Job ID Coverage
  Test
passed flatpak #45836

00:34:00

failed flatpak #45761

00:34:31

 
  Review
passed review #45762

00:09:13

manual stop_review #45763
allowed to fail manual
 
  Cross Distro
passed fedora:rawhide #45764

00:06:19