Close #3013 - re-enable test with upgrade of core libraries

Author: Myron Scott

clustered/integration-test/src/test/java/org/ehcache/clustered/replication/DuplicateTest.java

@@ -31,7 +31,6 @@
 import org.junit.After;
 import org.junit.Before;
 import org.junit.ClassRule;
-import org.junit.Ignore;
 import org.junit.Test;
 import org.terracotta.testing.rules.Cluster;
 
@@ -53,7 +52,6 @@
 import static org.hamcrest.Matchers.notNullValue;
 import static org.junit.Assume.assumeThat;
 
-@Ignore("https://github.com/ehcache/ehcache3/issues/3013")
 public class DuplicateTest {
 
   private PersistentCacheManager cacheManager;