Add gnocchi metadata for memcache security strategy

Change-Id: I3942e861ecce2c75577ed7c0a9c8d5d706e77a73
Related-Prod: PROD-23561
diff --git a/gnocchi/server/single.yml b/gnocchi/server/single.yml
index c4e1547..43a2c9d 100644
--- a/gnocchi/server/single.yml
+++ b/gnocchi/server/single.yml
@@ -10,3 +10,8 @@
       metricd:
         metric_processing_delay: 15
         metric_reporting_delay: 30
+      cache:
+        security:
+          enabled: ${_param:gnocchi_memcache_security_enabled}
+          strategy: ${_param:openstack_memcache_security_strategy}
+          secret_key: ${_param:gnocchi_memcache_secret_key}