ensure ca.pem makes it to multi-masters

roles/kubernetes/secrets/tasks/gen_certs.yml

@@ -21,7 +21,7 @@
   notify: set secret_changed
 
 - set_fact:
-    master_certs: ['ca-key.pem', 'admin.pem', 'admin-key.pem', 'apiserver-key.pem', 'apiserver.pem']
+    master_certs: ['ca.pem', 'ca-key.pem', 'admin.pem', 'admin-key.pem', 'apiserver-key.pem', 'apiserver.pem']
     node_certs: ['ca.pem', 'node.pem', 'node-key.pem']
 
 - name: certs | Get the certs from first master