ci: Add a fedora build job

We currently use a setup modelled after the flatpak CI workflow,
where we produce extension bundles and expose them as artifacts
for easy testing.

It still makes sense to test a regular build though, in particular
as that can include classic mode support.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/merge_requests/186>

.gitlab-ci.yml

@@ -130,3 +130,16 @@ build-bundles:
     expose_as: 'Get Extension bundles here'
     paths:
       - zip-files/
+
+fedora-build:
+  extends:
+    - .fdo.distribution-image@fedora
+    - .gnome-shell-extensions.fedora:34
+  stage: build
+  needs:
+    - build-fedora-container
+  script:
+    - meson setup build --werror -Dextension_set=all -Dclassic=true
+    - meson compile -C build
+    - meson test -C build
+    - meson install -C build