Upgrade elasticsearch-rest-client to 6.5.1

According to the release notes [1], there are no REST client related
bug fixes in this release. This is just to keep up to date with the
latest version.

Also update ElasticContainer to use version 6.5.1.

[1] https://www.elastic.co/guide/en/elasticsearch/reference/current/release-notes-6.5.1.html

Change-Id: I04a6c545b8d2e3394e1d02431394d4861244ed30
diff --git a/WORKSPACE b/WORKSPACE
index 6a1228c..5bd8a19 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -896,8 +896,8 @@
 # and httpasyncclient as necessary.
 maven_jar(
     name = "elasticsearch-rest-client",
-    artifact = "org.elasticsearch.client:elasticsearch-rest-client:6.5.0",
-    sha1 = "241436d27cf65b84d17126dc7b6b947e8e2c173c",
+    artifact = "org.elasticsearch.client:elasticsearch-rest-client:6.5.1",
+    sha1 = "d87892e24ef361b9fff5435246b0f0b8f4561fe8",
 )
 
 JACKSON_VERSION = "2.9.7"
diff --git a/gerrit-elasticsearch/src/test/java/com/google/gerrit/elasticsearch/ElasticContainer.java b/gerrit-elasticsearch/src/test/java/com/google/gerrit/elasticsearch/ElasticContainer.java
index 55ebd5d..7f50bbd 100644
--- a/gerrit-elasticsearch/src/test/java/com/google/gerrit/elasticsearch/ElasticContainer.java
+++ b/gerrit-elasticsearch/src/test/java/com/google/gerrit/elasticsearch/ElasticContainer.java
@@ -53,7 +53,7 @@
       case V6_4:
         return "docker.elastic.co/elasticsearch/elasticsearch-oss:6.4.3";
       case V6_5:
-        return "docker.elastic.co/elasticsearch/elasticsearch-oss:6.5.0";
+        return "docker.elastic.co/elasticsearch/elasticsearch-oss:6.5.1";
     }
     throw new IllegalStateException("No tests for version: " + version.name());
   }