HADOOP-19617. Fix Junit Test Error.

Author: vinayakumarb

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-applications-distributedshell/src/test/java/org/apache/hadoop/yarn/applications/distributedshell/DistributedShellBaseTest.java

@@ -33,6 +33,7 @@
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Supplier;
 
+import org.apache.hadoop.security.UserGroupInformation;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeEach;
@@ -545,6 +546,13 @@ protected void setupInternal(int numNodeManagers,
         getTimelineVersion());
     // setup the configuration of relevant for each TimelineService version.
     customizeConfiguration(conf);
+
+    String nodeLabels = "file:///tmp/hadoop-yarn-" +
+        UserGroupInformation.getCurrentUser().getShortUserName() +
+        "/node-labels";
+    java.nio.file.Path path = Paths.get(nodeLabels);
+    Files.deleteIfExists(path);
+
     // setup the yarn cluster.
     setUpYarnCluster(numNodeManagers, conf);
   }