trued toi fix unit tests

Author: kerryjiang

tests/Test/DataTypesTest.cs

@@ -243,7 +243,7 @@ private async Task TestDataType<TDateType>(string tableName, TDateType currentVa
             command.CommandText = $"select value from {tableName} where id = @id";
             command.Parameters.AddWithValue("@id", id);
 
-            MySqlDataReader reader = await command.ExecuteReaderAsync() as MySqlDataReader;
+            using var reader = await command.ExecuteReaderAsync() as MySqlDataReader;
 
             Assert.True(await reader.ReadAsync());