Add missing change for sniffer page

Related to #21737

docs/java-rest/sniffer.asciidoc

@@ -8,6 +8,8 @@ Nodes Info api and uses jackson to parse the obtained json response.
 
 Compatible with Elasticsearch 2.x and onwards.
 
+=== Maven Repository
+
 The low-level REST client is subject to the same release cycle as
 elasticsearch. Replace the version with the desired sniffer version, first
 released with `5.0.0-alpha4`. There is no relation between the sniffer version
@@ -15,7 +17,7 @@ and the elasticsearch version that the client can communicate with. Sniffer
 supports fetching the nodes list from elasticsearch 2.x and onwards.
 
 
-=== Maven coordinates
+==== Maven configuration
 
 Here is how you can configure the dependency using maven as a dependency manager.
 Add the following to your `pom.xml` file:
@@ -29,7 +31,7 @@ Add the following to your `pom.xml` file:
 </dependency>
 --------------------------------------------------
 
-=== Gradle coordinates
+==== Gradle configuration
 
 Here is how you can configure the dependency using gradle as a dependency manager.
 Add the following to your `build.gradle` file:
@@ -37,7 +39,7 @@ Add the following to your `build.gradle` file:
 ["source","groovy",subs="attributes"]
 --------------------------------------------------
 dependencies {
-    compile group: 'org.elasticsearch.client', name: 'sniffer', version: '{version}'
+    compile 'org.elasticsearch.client:sniffer:{version}'
 }
 --------------------------------------------------