Add helm.repositories back to argocd-cm.yaml (#2314)

docs/operator-manual/argocd-cm.yaml

@@ -56,6 +56,7 @@ data:
 
   # Git repositories configure Argo CD with (optional).
   # This list is updated when configuring/removing repos from the UI/CLI
+  # Note: 'type: helm' field is supported in v1.3+. Use 'helm.repositories' for older versions.
   repositories: |
     - url: https://github.com/argoproj/my-private-repository
       passwordSecret:
@@ -80,6 +81,19 @@ data:
         name: my-secret
         key: password
 
+  # Non-standard and private Helm repositories (deprecated in 1.3).
+  helm.repositories: |
+    - url: https://storage.googleapis.com/istio-prerelease/daily-build/master-latest-daily/charts
+      name: istio.io
+    - url: https://my-private-chart-repo.internal
+      name: private-repo
+      usernameSecret:
+        name: my-secret
+        key: username
+      passwordSecret:
+        name: my-secret
+        key: password
+
   # Configuration to customize resource behavior (optional). Keys are in the form: group/Kind.
   resource.customizations: |
     admissionregistration.k8s.io/MutatingWebhookConfiguration: