ElasticContainer: Upgrade V6_8 to elasticsearch 6.8.5

Change-Id: Ibb8552b468ada0cf227de339a1ce9860b5c932e6
diff --git a/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java b/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java
index 73e7eca..c15f1a7 100644
--- a/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java
+++ b/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java
@@ -51,7 +51,7 @@
       case V6_7:
         return "blacktop/elasticsearch:6.7.2";
       case V6_8:
-        return "blacktop/elasticsearch:6.8.4";
+        return "blacktop/elasticsearch:6.8.5";
       case V7_0:
         return "blacktop/elasticsearch:7.0.1";
       case V7_1: