HDFS-17770. TestRouterRpcSingleNS#testSaveNamespace should leave safemode after finishing. (#7609) Contributed by farmmamba.

* HDFS-17770. TestRouterRpcSingleNS#testSaveNamespace should leave safemode after finishing.

Reviewed-by: Jian Zhang <keepromise@apache.org>
Signed-off-by: Shilun Fan <slfan1989@apache.org>

hadoop-hdfs-project/hadoop-hdfs-rbf/src/test/java/org/apache/hadoop/hdfs/server/federation/router/TestRouterRpcSingleNS.java

@@ -205,7 +205,9 @@ public class TestRouterRpcSingleNS {
     cluster.getCluster().getFileSystem()
         .setSafeMode(SafeModeAction.ENTER);
     Boolean saveNamespace = routerProtocol.saveNamespace(0, 0);
-
     assertTrue(saveNamespace);
+    // Leave safe mode after saving the namespace.
+    cluster.getCluster().getFileSystem()
+        .setSafeMode(SafeModeAction.LEAVE);
   }
 }