Configuration is the first step of the lifetime of a context, after
creation; it's here where argc/argv is processed, and it's determined
what kind of compositor, etc, it is going to be.
The tests always run as Wayand compositors, so the configuration is
quite simple, but will involve more steps later on.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1861>
This introduces a MetaContext implementation aimed to be used for test
cases, with as little boiler plate as possible needed in the test.
It currently doesn't do anything, just fills out the GObject boiler
plate and sets a name.
Build it into every core test, for compilation, even though it isn't
used anywhere yet.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1861>
