root-app: add ignoreDifferences for Application finalizers

ArgoCD child apps (e.g. kyverno) get extra finalizers added at runtime,
causing root app-of-apps to show OutOfSync perpetually. Ignore
/metadata/finalizers drift on Application resources.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

root-app.yaml

@@ -12,6 +12,11 @@ spec:
   destination:
     server: https://kubernetes.default.svc
     namespace: argocd
+  ignoreDifferences:
+    - group: argoproj.io
+      kind: Application
+      jsonPointers:
+        - /metadata/finalizers
   syncPolicy:
     automated:
       prune: true