fix scala style error

core/src/main/scala/org/apache/spark/scheduler/TaskSetManager.scala

@@ -83,7 +83,7 @@ private[spark] class TaskSetManager(
   // be re-run because the missing map data needs to be regenerated first.
   val successful = new Array[Boolean](numTasks)
   private val numFailures = new Array[Int](numTasks)
-  
+
   // Add the tid of task into this HashSet when the task is killed by other attempt tasks.
   // This happened while we set the `spark.speculation` to true. The task killed by others
   // should not resubmit while executor lost.