[polari] ci: Add back a fedora job

[Marge Bot <marge-bot src gnome org>]

commit 23be62eeedbfb73382316c7c6c8f332e8e077d18
Author: Florian Müllner <fmuellner gnome org>
Date:   Sat Aug 28 16:44:39 2021 +0200

    ci: Add back a fedora job
    
    We disabled and ultimately removed the distro build when switching
    our CI to flatpak. The latter has many advantages (canonical upstream
    environment, installable artifact, gnome-nightly build), but it does
    make it harder to run additional checks.
    
    That is easier with a manual build from a regular distro image, so
    add back such a job.
    
    Part-of: <https://gitlab.gnome.org/GNOME/polari/-/merge_requests/220>

 .gitlab-ci.yml | 13 +++++++++++++
 1 file changed, 13 insertions(+)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 9b982c12..65d85a98 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -161,6 +161,19 @@ nightly:
   variables:
     BUNDLES: '$BUNDLE'
 
+fedora-build:
+  extends:
+    - .fdo.distribution-image@fedora
+    - .polari.fedora:34
+  stage: build
+  needs:
+    - build-fedora-container
+  script:
+    - meson setup build --werror
+    - meson compile -C build
+    - meson test -C build
+    - meson install -C build
+
 check-flatpak-deps:
   image:
     name: ghcr.io/flathub/flatpak-external-data-checker