app row: Make version arrows smaller

Break up the labels that form the version strong (1.2.3 -> 1.2.4) so
that the arrow is in a separate label. This makes it possible to control
the arrow size separately, so that it's not humongous with new
Cantarell.
1 job for wip/kalev/smaller-arrows in 3 minutes and 20 seconds (queued for 3 seconds)
latest
Status Job ID Name Coverage
  Build
passed #113238
build-gnome-software

00:03:20