CHORE(tekton): enable auto-prune for tekton-ci-cd

- Enable prune: true to auto-delete orphaned resources
- Add finalizers for proper resource cleanup
- Add PrunePropagationPolicy and PruneLast sync options
- Set revisionHistoryLimit to 10

tekton/ci-cd/argocd.yaml

@@ -3,8 +3,8 @@ kind: Application
 metadata:
   name: tekton-ci-cd
   namespace: argocd
-  annotations:
+  finalizers:
-    argocd.argoproj.io/compare-options: IgnoreExtraneous
+  - resources-finalizer.argocd.argoproj.io
 spec:
   project: default
   source:
@@ -16,13 +16,17 @@ spec:
     namespace: tekton-pipelines
   syncPolicy:
     automated:
-      prune: false
+      prune: true
       selfHeal: true
+      allowEmpty: false
     syncOptions:
     - CreateNamespace=true
+    - PrunePropagationPolicy=foreground
+    - PruneLast=true
     retry:
       limit: 5
       backoff:
         duration: 5s
         factor: 2
         maxDuration: 3m
+  revisionHistoryLimit: 10