Fix param name for docker elasticseach image

Change-Id: I06c088a4328583baaccc0422c0bc7c739d9356f7
diff --git a/docker/swarm/stack/elasticsearch.yml b/docker/swarm/stack/elasticsearch.yml
index ae63d5c..a5fdd29 100644
--- a/docker/swarm/stack/elasticsearch.yml
+++ b/docker/swarm/stack/elasticsearch.yml
@@ -17,7 +17,7 @@
             discovery.type: ${_param:elasticsearch_discovery_type}
           service:
             cluster:
-              image: ${_param:docker_image_oss_elasticsearch}
+              image: ${_param:docker_image_elasticsearch}
               deploy:
                 replicas: ${_param:elasticsearch_replicas}
                 restart_policy: