remove unnecessary import

Author: xiepengjie

sql/hive/src/main/scala/org/apache/spark/sql/hive/TableReader.scala

@@ -20,7 +20,6 @@ package org.apache.spark.sql.hive
 import java.util.Properties
 
 import scala.collection.JavaConverters._
-import scala.util.{Failure, Success, Try}
 
 import org.apache.hadoop.conf.Configuration
 import org.apache.hadoop.fs.{Path, PathFilter}