Put the errors in a scrolled window

it also cleans up the stylecontext errors before displaying them
4 jobs for master in 30 minutes and 18 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Lint
passed #388401
rustfmt

00:00:29

 
  Test
passed #388402
flatpak

00:29:05

 
  Review
passed #388403
review

00:00:43

manual #388404
allowed to fail manual
stop_review