[SQL] remove unnecessary import

Author: Jacky Li <jacky.likun@huawei.com>

Closes #3585 from jackylk/remove and squashes the following commits:

045423d [Jacky Li] remove unnecessary import

sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala

@@ -22,7 +22,6 @@ import java.util.TimeZone
 import org.scalatest.BeforeAndAfterAll
 
 import org.apache.spark.sql.catalyst.errors.TreeNodeException
-import org.apache.spark.sql.catalyst.expressions._
 import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan
 
 /* Implicits */