Gather facts for provision playbook

Provision tasks use facts like ansible_hostname and few others.
W/o gathering facts, those expire, and the provision playbook cannot
be reapplied in order to update the existing heat stack.
Refresh the facts cache by specifying gather_facts: true.

Signed-off-by: Bogdan Dobrelya <bdobreli@redhat.com>

playbooks/provisioning/openstack/provision-openstack.yml

@@ -1,5 +1,6 @@
 ---
 - hosts: localhost
+  gather_facts: True
   pre_tasks:
   - include: pre_tasks.yml
   roles: