Update Core

Src/Asp.NetCore2/SqlSeverTest/SqlSugar/Realization/SqlServer/SqlBuilder/SqlServerBlukCopy.cs

@@ -1,7 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Data;
-using System.Data.SqlClient;
+using Microsoft.Data.SqlClient;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;