[bugfix] Remove a duplicate dependency that was introduced in aaeab2b

Author: adamretter

exist-core/pom.xml

@@ -614,11 +614,6 @@
             <artifactId>xmlunit-matchers</artifactId>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>org.xmlunit</groupId>
-            <artifactId>xmlunit-matchers</artifactId>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>com.googlecode.junit-toolbox</groupId>
             <artifactId>junit-toolbox</artifactId>