chore(backstage): Added SA for backstage to ArgoCD

clusters/artemis/apps/mailu/catalog.yaml

@@ -0,0 +1,18 @@
+---
+apiVersion: backstage.io/v1alpha1
+kind: Component
+metadata:
+  name: mailu
+  description: "Self-hosted mail server"
+  links:
+    - url: https://mail.dgse.cloud
+      title: Mail Server
+      icon: web
+  annotations:
+    argocd/app-name: mailu
+    argocd/app-namespace: mailu
+spec:
+  type: service
+  lifecycle: production
+  owner: owners
+  system: artemis-cluster