artistalbumswidget: Pass application around

Cleanup some arguments by passing the application object instead.
4 jobs for wip/mschraal/search-cleanups in 8 minutes and 49 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Check
passed #370526
flake8

00:02:07

 
  Build Flatpak
passed #370527
flatpak

00:05:32

 
  Deploy
passed #370528
review

00:00:32

passed #370529
allowed to fail manual
stop_review

00:00:37