hot fix: add missing import

Author: cloud-fan

core/src/main/scala/org/apache/spark/internal/config/package.scala

@@ -21,6 +21,7 @@ import java.util.concurrent.TimeUnit
 
 import org.apache.spark.launcher.SparkLauncher
 import org.apache.spark.network.util.ByteUnit
+import org.apache.spark.unsafe.array.ByteArrayMethods
 import org.apache.spark.util.Utils
 
 package object config {