.gitignore: ignore mo files

3 jobs for master in 3 minutes and 17 seconds
Status Job ID Name Coverage
  Build
passed #367613260
build-cmake

00:02:48

failed #725442844
build-meson

00:00:29

failed #367613262
build-meson

00:01:10

 
Name Stage Failure
failed
build-meson Build
Executing glib-2.64.5-r0.trigger
Executing shared-mime-info-1.15-r0.trigger
Executing gdk-pixbuf-2.40.0-r2.trigger
Executing gtk-update-icon-cache-2.24.32-r2.trigger
Executing graphviz-2.44.0-r0.trigger
OK: 577 MiB in 234 packages
$ pip3 install meson
/bin/sh: eval: line 106: pip3: not found
ERROR: Job failed: exit code 127