Support authentication for custom CNI Helm repositories (#13294)

* Add authentication support for custom CNI Helm repository

Pass optional Helm repository username and password values to the custom CNI chart configuration. These values use default(omit) so authentication fields are only included when explicitly defined by the user.

* Document custom CNI Helm repository authentication variables

Add commented sample variables for configuring a username and password when the custom CNI Helm repository requires authentication.

* Address Copilot documentation feedback

Document paired repository credentials and secure password storage.
Remove authentication placeholders from the public Cilium example.

inventory/sample/group_vars/k8s_cluster/k8s-net-custom-cni.yml

@@ -30,6 +30,14 @@
 ## Helm repository URL
 # custom_cni_chart_repository_url: ""
 #
+## Helm repository username, if authentication is required
+## Username and password must be defined together
+# custom_cni_chart_repository_username: "<helm_repository_username>"
+#
+## Helm repository password, if authentication is required
+## Store sensitive values securely, for example using Ansible Vault
+# custom_cni_chart_repository_password: "<helm_repository_password>"
+#
 ## Helm chart reference - path to the chart in the repository
 # custom_cni_chart_ref: ""
 #

roles/network_plugin/custom_cni/meta/main.yml

@@ -17,3 +17,5 @@ dependencies:
     repositories:
       - name: "{{ custom_cni_chart_repository_name }}"
         url: "{{ custom_cni_chart_repository_url }}"
+        username: "{{ custom_cni_chart_repository_username | default(omit) }}"
+        password: "{{ custom_cni_chart_repository_password | default(omit) }}"