ui: Fix translatable attribute in login_flow

It takes “yes,” not “true”.
4 jobs for piotrdrag/fix-translatable-true in 20 minutes and 4 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Check
passed #278280
check

00:00:24

 
  Test
passed #278281
flatpak

00:17:56

 
  Review
passed #278282
review

00:00:44

passed #278283
manual
stop_review

00:00:58