remove unused imports.

Author: hfutatzhanghb

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestReconstructStripedFileWithValidator.java

@@ -21,14 +21,11 @@
 import org.apache.hadoop.hdfs.server.datanode.DataNodeFaultInjector;
 import org.apache.hadoop.hdfs.server.datanode.metrics.DataNodeMetrics;
 import org.junit.Assert;
-import org.junit.Rule;
 import org.junit.Test;
-import org.junit.rules.Timeout;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.nio.ByteBuffer;
-import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 /**