[Octavia] octavia_identity v3 updates

Partially revert I59abe186cc170fe1a30a5e8bc46ba3d39cefa1c1
to return setting required for proper configs in _keystone.conf

Change-Id: I86dcf964ba4549a6ef8bb9a08371fd2cd8fd26d4
Related-PROD: PROD-24747
(cherry picked from commit 463c32968d4b87fcc8d932a85cd0880cf8670486)
diff --git a/keystone/client/v3/service/octavia.yml b/keystone/client/v3/service/octavia.yml
index c02a6b8..eca4975 100644
--- a/keystone/client/v3/service/octavia.yml
+++ b/keystone/client/v3/service/octavia.yml
@@ -8,6 +8,12 @@
     octavia_service_protocol: http
   keystone:
     client:
+      server:
+        octavia_identity:
+          admin:
+            api_version: ''
+            user_domain_name: 'Default'
+            project_domain_name: 'Default'
       resources:
         v3:
           roles: