sharing: Ellipsize the labels

This helps ensuring the panel fits in narrow windows.
11 jobs for adaptive-sharing in 3 minutes and 6 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Build
passed #258085
build

00:01:29

 
  Test
passed #258087
asan

00:01:35

passed #258086
test

00:01:11

 
  Manual
manual #258092
allowed to fail manual
armv8
manual #258088
allowed to fail manual
flatpak
manual #258091
allowed to fail manual
msan
manual #258093
allowed to fail manual
ppc64le
manual #258089
allowed to fail manual
tsan
manual #258090
allowed to fail manual
ubsan
 
  Review
manual #258094
allowed to fail manual
review
manual #258095
allowed to fail manual
stop_review