Implement fix for Octavia host group name

Octavia was hitting bug
https://bugs.launchpad.net/openstack-ansible/+bug/1623584
This implements a fix.

Change-Id: Ib892d85135697bc283394460ce33b31b4ffb3080

etc/openstack_deploy/conf.d/octavia.yml.aio

@@ -1,4 +1,4 @@
 # The controller host that the octavia control plane will be run on
-octavia_hosts:
+octavia-infra_hosts:
   aio1:
     ip: 172.29.236.100

playbooks/inventory/env.d/octavia.yml

@@ -44,6 +44,6 @@ physical_skel:
   octavia-infra_containers:
     belongs_to:
       - all_containers
-  octavia_hosts:
+  octavia-infra_hosts:
     belongs_to:
       - hosts

releasenotes/notes/add-octavia-to-repo-f9d0fd8cee969181.yaml

@@ -2,4 +2,4 @@
 features:
   - Experimental support has been added to allow the deployment of
     the OpenStack Octavia Load Balancing service when hosts are present
-    in the host group ``octavia_hosts``.
+    in the host group ``octavia-infra_hosts``.

tests/test_inventory.py

@@ -257,7 +257,7 @@ class TestAnsibleInventoryFormatConstraints(unittest.TestCase):
         'magnum-infra_hosts',
         'magnum_all',
         'magnum_container',
-        'octavia_hosts',
+        'octavia-infra_hosts',
         'octavia_all',
         'octavia-api',
         'octavia_server_container',
@@ -265,6 +265,7 @@ class TestAnsibleInventoryFormatConstraints(unittest.TestCase):
         'octavia-housekeeping',
         'octavia-health-manager',
         'octavia-infra_containers',
+        'octavia-infra_all',
         'trove_all',
         'trove_api',
         'trove_conductor',