HDFS-15344. DataNode#checkSuperuserPrivilege should use UGI#getGroups after HADOOP-13442. (#2004)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java

@@ -1082,7 +1082,7 @@ public class DataNode extends ReconfigurableBase
     }
 
     // Is the user a member of the super group?
-    List<String> groups = Arrays.asList(callerUgi.getGroupNames());
+    List<String> groups = callerUgi.getGroups();
     if (groups.contains(supergroup)) {
       return;
     }