[SPARK-11974][CORE] Not all the temp dirs had been deleted when the JVM exits

deleting the temp dir like that

```

scala> import scala.collection.mutable
import scala.collection.mutable

scala> val a = mutable.Set(1,2,3,4,7,0,8,98,9)
a: scala.collection.mutable.Set[Int] = Set(0, 9, 1, 2, 3, 7, 4, 8, 98)

scala> a.foreach(x => {a.remove(x) })

scala> a.foreach(println(_))
98
```

You may not modify a collection while traversing or iterating over it.This can not delete all element of the collection

Author: Zhongshuai Pei <peizhongshuai@huawei.com>

Closes #9951 from DoingDone9/Bug_RemainDir.

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