fixed checkstyle violation

x-pack/plugin/enrich/qa/common/src/main/java/org/elasticsearch/test/enrich/CommonEnrichRestTestCase.java

@@ -25,7 +25,6 @@ import java.util.concurrent.TimeUnit;
 
 import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;
 import static org.hamcrest.Matchers.equalTo;
-import static org.hamcrest.Matchers.greaterThan;
 import static org.hamcrest.Matchers.greaterThanOrEqualTo;
 
 public abstract class CommonEnrichRestTestCase extends ESRestTestCase {