[SEBA-165] hide backend and policy_status for services which doesn't have those

Change-Id: I3e80f21cc5bacc727facd1dba2ed26d880778bf2
diff --git a/xos/synchronizer/config.yaml b/xos/synchronizer/config.yaml
index 6c59579..5b7a7bd 100644
--- a/xos/synchronizer/config.yaml
+++ b/xos/synchronizer/config.yaml
@@ -15,7 +15,7 @@
 
 
 name: volt
-core_version: ">=3.2.7"
+core_version: ">=3.2.8"
 required_models:
   - VOLTService
   - VOLTServiceInstance