CORD-1905 Wait for head node to become available

Change-Id: If9a531d67f4dcb1071c523aafc325875ba8bfbc8
(cherry picked from commit f8e46cdc110c34d418ea6a6867037d37f0822e63)
diff --git a/ansible/config-ssh-key.yml b/ansible/config-ssh-key.yml
index 0e31b8c..484b1ef 100644
--- a/ansible/config-ssh-key.yml
+++ b/ansible/config-ssh-key.yml
@@ -35,6 +35,12 @@
       register: config_pubkey
 
 - hosts: head
+  gather_facts: false
+  tasks:
+    - name: Wait for head node to be available
+      wait_for_connection:
+
+- hosts: head
   tasks:
     - name: Add config ssh key to head node
       authorized_key: