feat: add image update automation

cluster/base/apps.yaml

@@ -15,3 +15,29 @@ spec:
     name: flux-system
   timeout: 5m0s
   wait: true
+---
+apiVersion: image.toolkit.fluxcd.io/v1beta2
+kind: ImageUpdateAutomation
+metadata:
+  name: flux-system
+  namespace: flux-system
+spec:
+  git:
+    checkout:
+      ref:
+        branch: main
+    commit:
+      author:
+        email: fluxcdbot@users.noreply.github.com
+        name: fluxcdbot
+      messageTemplate: '{{range .Changed.Changes}}{{print .OldValue}} -> {{println
+        .NewValue}}{{end}}'
+    push:
+      branch: main
+  interval: 5m0s
+  sourceRef:
+    kind: GitRepository
+    name: flux-system
+  update:
+    path: cluster/base
+    strategy: Setters