CI: do not attempt to test GL-renderer

Because of https://gitlab.freedesktop.org/mesa/mesa/issues/2219 it would crash,
so disable GL-renderer.

https://gitlab.freedesktop.org/wayland/weston/issues/358 shall revert this.
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

.gitlab-ci.yml

@@ -69,6 +69,7 @@ build-native-meson-default-options:
     MESON_OPTIONS: >
       -Dwerror=true
       -Ddoc=true
+      -Dtest-gl-renderer=false
   extends: .build-native-meson
 
 build-native-meson-no-gl-renderer: