for anonymous callers

constructed() was simply creating an action group which
is never used.

And fix a memory leak.

We didn't have bullseye images back then.

It used to work because the pipeline definitions had been
overriding `before_script`, which isn't the case anymore.

Fixes #213

The 'property-changed' and 'disconnect-reason' signals weren't disconnected on the
voice_call object cleanup, and callbacks would thus still be fired once a second
call happens, resulting in a crash.
Signed-off-by: Eugenio Paolantonio (g7) <me@medesimo.eu>

Fixes lintian warning `desktop-entry-lacks-main-category`

Closes #202

Closes #205

It got renamed in f6f9e3f0

Fixes #200

Added callaudiod to the Flatpak manifest so Calls builds again.

It got moved in f6f9e3f0

This makes sure we valiate desktop files

If there are translation in C files but not in POTFILES.in
fail the pipeline.