fix scalastyle

Author: Ngone51

core/src/main/scala/org/apache/spark/deploy/worker/Worker.scala

@@ -28,13 +28,14 @@ import scala.collection.mutable.{HashMap, HashSet, LinkedHashMap}
 import scala.concurrent.ExecutionContext
 import scala.util.Random
 import scala.util.control.NonFatal
+
 import org.apache.spark.{SecurityManager, SparkConf}
 import org.apache.spark.deploy.{Command, ExecutorDescription, ExecutorState}
 import org.apache.spark.deploy.DeployMessages._
 import org.apache.spark.deploy.ExternalShuffleService
 import org.apache.spark.deploy.master.{DriverState, Master}
 import org.apache.spark.deploy.worker.ui.WorkerWebUI
-import org.apache.spark.internal.{Logging, config}
+import org.apache.spark.internal.{config, Logging}
 import org.apache.spark.internal.config.Tests.IS_TESTING
 import org.apache.spark.internal.config.UI._
 import org.apache.spark.internal.config.Worker._