ElasticContainer: Upgrade V6_8 to elasticsearch 6.8.10

Change-Id: I208764b373bc46957e79a5c887b63ac28c79ff6f
diff --git a/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java b/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java
index e436db5..c20650f 100644
--- a/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java
+++ b/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java
@@ -43,7 +43,7 @@
       case V6_7:
         return "blacktop/elasticsearch:6.7.2";
       case V6_8:
-        return "blacktop/elasticsearch:6.8.9";
+        return "blacktop/elasticsearch:6.8.10";
       case V7_0:
         return "blacktop/elasticsearch:7.0.1";
       case V7_1: