[MPLUGIN-387] Bump xmlunit to 1.6

Author: slachiewicz

maven-plugin-tools-java/pom.xml

@@ -75,7 +75,7 @@
     <dependency>
       <groupId>xmlunit</groupId>
       <artifactId>xmlunit</artifactId>
-      <version>1.3</version>
+      <version>1.6</version>
       <scope>test</scope>
     </dependency>
   </dependencies>