Update answers.sls to include openvswitch neutron SDN backend.

environment/answers.sls

@@ -168,9 +168,9 @@ networking:
 
 
 ## neutron networking backend.  Valid values are networking-ovn
-## or linuxbridge
+## or linuxbridge or openvswitch
 neutron:
-  backend: networking-ovn
+  backend: openvswitch
 
 ## nova configuration options.  Ref: https://docs.openstack.org/nova/latest/configuration/config.html
 nova: