Fix the openstack_release variable in all.yml

In the master branch, we should use 3.0.0 release version

Change-Id: I3b10307c2072c28ea00e26fbbdf6723ebc318f30

ansible/group_vars/all.yml

@@ -160,7 +160,7 @@ admin_protocol: "http"
 ####################
 # OpenStack options
 ####################
-openstack_release: "2.0.0"
+openstack_release: "3.0.0"
 openstack_logging_debug: "False"
 
 openstack_region_name: "RegionOne"