PostgreSQL数据库，DateTime类型映射不正确

#### 问题描述及重现代码：
DateTime类型创建时映射成了timestamptz，而实际应该timestamp
```c#
public class CollectionData
{
///
/// 实验时间
///
[Column(Name = "sampleTime")]
public DateTime SampleTime { get; set; }
}

var fsql = new FreeSqlBuilder()
.UseConnectionString(DataType.PostgreSQL, strSqlConn)
.UseAutoSyncStructure(true)
.UseNameConvert(FreeSql.Internal.NameConvertType.ToLower)
.Build();

var date = new CollectionData()
{
SampleNo = "123456",
SampleIndex = 1,
SampleType = "实验",
SampleTime = DateTime.Now,
};

int row = fsql.Insert(date).ExecuteAffrows();
```

#### 数据库版本
FreeSql3.5.102
FreeSql.Provider.PostgreSQL3.5.102

#### 安装的Nuget包

#### .net framework/. net core？ 及具体版本
.net8