Reduce max_connections and innodb_buffer_pool_size for K8S envs

To reduce RAM usage , as far as Galera is used only for Grafana
in kubernetes environments.

Change-Id: I6e45e2e4ce9a67d5c20539049e97807338d4f49e
diff --git a/classes/cluster/sl_k8s_contrail/stacklight/server.yml b/classes/cluster/sl_k8s_contrail/stacklight/server.yml
index 8b30a14..89ae877 100644
--- a/classes/cluster/sl_k8s_contrail/stacklight/server.yml
+++ b/classes/cluster/sl_k8s_contrail/stacklight/server.yml
@@ -43,6 +43,8 @@
     keepalived_prometheus_vip_interface: ens4
     # Galera
     openstack_version: ocata
+    galera_innodb_buffer_pool_size: 1024M
+    galera_max_connections: 200
     # Grafana
     grafana_database_type: mysql
     grafana_database_host: ${_param:cluster_vip_address}