Serialize AllNodesDeployment and UpdateWorkflow

Otherwise there may be a race between updating the hiera
and running the UpdateWorkflow

Change-Id: I22cd893e0db3df6d39504fbd61d7d9024cebb1c5
Related-Bug: 1631297

overcloud.j2.yaml

@@ -487,6 +487,10 @@ resources:
 
   UpdateWorkflow:
     type: OS::TripleO::Tasks::UpdateWorkflow
+    depends_on:
+{% for role in roles %}
+      - {{role.name}}AllNodesDeployment
+{% endfor %}
     properties:
       servers:
 {% for role in roles %}