lambda 当中 添加日期类型转换

在lambda 当中 添加日期类型转换  需要写扩展方法

https://learn.microsoft.com/en-us/ef/core/providers/sql-server/functions

https://learn.microsoft.com/en-us/ef/core/modeling/value-conversions?tabs=data-annotations

https://stackoverflow.com/questions/68728498/convert-string-to-datetime-in-linq-query-with-entity-framework-core