AMBARI-14513. Bump up Spark version to 1.6 in HDP 2.4 (Jeff Zhang via smohanty)

ambari-server/src/main/resources/stacks/HDP/2.4/services/SPARK/metainfo.xml

@@ -23,7 +23,7 @@
     <services>
         <service>
           <name>SPARK</name>
-          <version>1.5.2.2.4</version>
+          <version>1.6.0.2.4</version>
         </service>
     </services>
 </metainfo>