CI: Add more dependencies to Ubuntu environment

These dependencies are the ones that `jhbuild sysdeps` is complaining
about. (And, installing them, we don't need to run `jhbuild sysdeps`
anymore.)

Closes #16.
4 jobs for fix-docker in 15 minutes and 30 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
passed #1969
fedora_clang

00:07:58

passed #1970
fedora_cppcheck

00:00:15

passed #1968
fedora_gcc

00:07:16

 
  Failure
skipped #1971
on_failure