[MINOR][SQL] Fix typo in CTAS plan argString

```
scala> sql("create table t as select 1").explain
== Physical Plan ==
ExecutedCommand CreateTableAsSelect [Database:default}, TableName: t, InsertIntoHiveTable]
+- Project [1 AS _c0#3]
   +- OneRowRelation$

scala> sc.version
res1: String = 1.6.0
```

Author: dongjoon-hyun

sql/hive/src/main/scala/org/apache/spark/sql/hive/execution/CreateHiveTableAsSelectCommand.scala

@@ -96,7 +96,7 @@ case class CreateHiveTableAsSelectCommand(
   }
 
   override def argString: String = {
-    s"[Database:${tableDesc.database}}, " +
+    s"[Database:${tableDesc.database}, " +
     s"TableName: ${tableDesc.identifier.table}, " +
     s"InsertIntoHiveTable]"
   }