display: Mark strings as translatable

Those were translatable before the "templating" of this section of the
panel.

Fixes: 8503dab5
11 jobs for wip/hadess/fix-display-translation in 4 minutes and 28 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Build
passed #228357
build

00:01:44

 
  Test
passed #228359
asan

00:02:43

passed #228358
test

00:02:43

 
  Manual
manual #228364
allowed to fail manual
armv8
manual #228360
allowed to fail manual
flatpak
manual #228363
allowed to fail manual
msan
manual #228365
allowed to fail manual
ppc64le
manual #228361
allowed to fail manual
tsan
manual #228362
allowed to fail manual
ubsan
 
  Review
manual #228366
allowed to fail manual
review
manual #228367
allowed to fail manual
stop_review