helm-template: allow users to disable wait-for-pods

It's possible that a Helm chart does *not* create any pods, such as in
the case if you're using Helm to manage all of your RBAC resources.

Change-Id: I98b8427b1f4b6a2f454c3f796fa8a6ad2d765c46

roles/helm-template/README.rst

@@ -11,6 +11,12 @@ already setup and the Helm executable is installed.
 
    Directory of the Helm chart.
 
+.. zuul:rolevar:: helm_wait_for_pods
+   :default: True
+
+   Determine if the role should wait for all pods to go up after it applies
+   the template.
+
 .. zuul:rolevar:: zuul_work_dir
    :default: {{ zuul.project.src_dir }}
 

roles/helm-template/defaults/main.yaml

@@ -1 +1,2 @@
+helm_wait_for_pods: true
 zuul_work_dir: "{{ zuul.project.src_dir }}"

roles/helm-template/tasks/main.yaml

@@ -18,4 +18,5 @@
 
 - name: Wait for all pods to become Ready
   include_role:
-    name: wait-for-pods
+    name: wait-for-pods
+  when: helm_wait_for_pods | bool