ci: Change the without-native-backend to not build with Wayland too

There are two common ways of building mutter: With both the native
backend and Wayland support (most common, used by most Linux distributions), and
without the native backend and Wayland support (as is done by some
BSD*s).

To catch compilation errors in both these common build configurations,
change the no-native-backend build phase to also not build with Wayland
support.

This also disables building mutter tests, as tests depend on Wayland to
run.

GNOME/mutter!837
5 jobs for !837 with wip/ci-no-native-also-no-wayland in 12 minutes and 54 seconds (queued for 2 seconds)
detached
Status Job ID Name Coverage
  Review
passed #460900
check-commit-log

00:00:21

 
  Build
passed #460901
build-mutter

00:09:24

passed #460902
build-without-native-backend-and-wayland

00:01:24

 
  Test
passed #460904
can-build-gnome-shell

00:01:43

passed #460903
test-mutter

00:03:07