- using new orm api, change some related logics
- newer orm api has the concept of TxOrmer, for purpose of transaction
handling. A transaction ormer in v2 is a stateful object, it should be
dropped after using. A Ormer object is stateless and thread(routine)
safe, and should not be used for transaction handling. More details
count be found at official doc:
https://beego.me/docs/mvc/model/orm.md, and pr note: https://github.com/mindoc-org/mindoc/pull/662#issuecomment-807040262