gitlabci: Add review apps.

This makes it able to show a link pointing to the bundle in Merge Requests.

.gitlab-ci.yml

@@ -1,6 +1,7 @@
 stages:
   - test
   - lint
+  - review
 
 .cargo_test_template: &cargo_test
     stage: test
@@ -83,6 +84,34 @@ flatpak:
           - .flatpak-builder/cache/
           - target/
 
+review:
+    stage: review
+    dependencies:
+        - flatpak
+    script:
+        - echo "Generating flatpak deployment"
+    artifacts:
+        paths:
+            - hammond-dev.flatpak
+        expire_in: 30 days
+    environment:
+        name: review/$CI_COMMIT_REF_NAME
+        url: https://gitlab.gnome.org/$CI_PROJECT_PATH/-/jobs/$CI_JOB_ID/artifacts/raw/${BUNDLE}
+        on_stop: stop_review
+    except:
+        - master@World/hammond
+
+stop_review:
+    stage: review
+    script:
+        - echo "Stopping flatpak deployment"
+    when: manual
+    environment:
+        name: review/$CI_COMMIT_REF_NAME
+        action: stop
+    except:
+        - master@World/hammond
+
 # Configure and run rustfmt on nightly
 # Exits and builds fails if on bad format
 rustfmt: