Fix import order and scalastyle (#375)

Test with ./dev/scalastyle

Author: ash211

resource-managers/kubernetes/core/src/test/scala/org/apache/spark/deploy/kubernetes/InitContainerResourceStagingServerSecretPluginSuite.scala

@@ -16,11 +16,11 @@
  */
 package org.apache.spark.deploy.kubernetes
 
-import org.scalatest.BeforeAndAfter
 import io.fabric8.kubernetes.api.model._
-import org.apache.spark.deploy.kubernetes.constants._
-
+import org.scalatest.BeforeAndAfter
 import scala.collection.JavaConverters._
+
+import org.apache.spark.deploy.kubernetes.constants._
 import org.apache.spark.SparkFunSuite
 
 class InitContainerResourceStagingServerSecretPluginSuite extends SparkFunSuite with BeforeAndAfter{

resource-managers/kubernetes/core/src/test/scala/org/apache/spark/deploy/kubernetes/SparkPodInitContainerBootstrapSuite.scala

@@ -16,11 +16,11 @@
  */
 package org.apache.spark.deploy.kubernetes
 
-import org.scalatest.BeforeAndAfter
 import io.fabric8.kubernetes.api.model._
-import org.apache.spark.deploy.kubernetes.constants._
-
+import org.scalatest.BeforeAndAfter
 import scala.collection.JavaConverters._
+
+import org.apache.spark.deploy.kubernetes.constants._
 import org.apache.spark.SparkFunSuite
 
 class SparkPodInitContainerBootstrapSuite extends SparkFunSuite with BeforeAndAfter {