the sample compute node play book is moved out of the main repo to a file in the role

Change-Id: Ibcbb4cc0f8dadcc9bd8f7888ccd41799cb343a10
diff --git a/roles/head-node/tasks/main.yml b/roles/head-node/tasks/main.yml
index 820964a..21495f1 100644
--- a/roles/head-node/tasks/main.yml
+++ b/roles/head-node/tasks/main.yml
@@ -20,7 +20,6 @@
   command: cp -r /tmp/ansible.maas/{{ item }} /etc/maas/ansible/{{ item }}
   with_items:
     - roles
-    - compute-node.yml
 
 - name: Ensure Compute Node Playbook
   become: yes