Enable daily builds

zuul.d/zuul.yaml

@@ -26,12 +26,15 @@
       jobs:
         - kaniko-build-image-debian-systemd-stretch
         - kaniko-build-image-debian-systemd-buster
-    # TODO once available:
-    # check pipeline: use approval reporter (zuul)
-    # set approvals_required to 2: zuul & one developer (gitlab)
-    # use gate pipeline with approval requirement & merge reporter (rebuild the image)
-    # promote pipeline with merged requirement (add the 'latest' tag without rebuilding the image)
+    # TODO:
+    # - check pipeline: use build status reporter (once available)
+    # - use gate pipeline with build status requirement & merge reporter (rebuild the image)
+    # - promote pipeline with merged requirement (add the 'latest' tag without rebuilding the image)
     promote:
       jobs:
         - kaniko-build-image-debian-systemd-stretch
         - kaniko-build-image-debian-systemd-buster
+    periodic-daily:
+      jobs:
+        - kaniko-build-image-debian-systemd-stretch
+        - kaniko-build-image-debian-systemd-buster