[SPARK-3873][TESTS] Import ordering fixes.

...src/test/scala/org/apache/spark/ContextCleanerSuite.scala

...ala/org/apache/spark/ExecutorAllocationManagerSuite.scala

core/src/test/scala/org/apache/spark/FailureSuite.scala

core/src/test/scala/org/apache/spark/FileServerSuite.scala

core/src/test/scala/org/apache/spark/FileSuite.scala

.../test/scala/org/apache/spark/HeartbeatReceiverSuite.scala

core/src/test/scala/org/apache/spark/LocalSparkContext.scala

...c/test/scala/org/apache/spark/MapOutputTrackerSuite.scala

core/src/test/scala/org/apache/spark/SSLOptionsSuite.scala

core/src/test/scala/org/apache/spark/ShuffleSuite.scala

core/src/test/scala/org/apache/spark/SortShuffleSuite.scala

core/src/test/scala/org/apache/spark/SparkConfSuite.scala

...c/test/scala/org/apache/spark/SparkContextInfoSuite.scala

...org/apache/spark/SparkContextSchedulerCreationSuite.scala

core/src/test/scala/org/apache/spark/SparkContextSuite.scala

core/src/test/scala/org/apache/spark/ThreadingSuite.scala

...la/org/apache/spark/api/python/PythonBroadcastSuite.scala

.../test/scala/org/apache/spark/deploy/DeployTestUtils.scala

...src/test/scala/org/apache/spark/deploy/IvyTestUtils.scala

...est/scala/org/apache/spark/deploy/JsonProtocolSuite.scala