Make dummy job mandatory

.gitlab/ci_templates/dummy_job.yml

@@ -5,4 +5,6 @@ dummy-job:
   - echo "nonetheless, useful for situations where CI rules would not trigger"
   - echo "a pipeline automatically, i.e. changes to renovate.json"
   - echo "(see https://open.greenhost.net/stackspin/wordpress-helm/-/merge_requests/127#note_38728)"
-  when: manual
+  # Setting this job to manual (optional) doesn't work when no other
+  # job is run.
+  # when: manual