tidb config: add txn-entry-size-limit (#5158)
tidb config: add txn-entry-size-limit (#5158)

* tidb config: add txn-entry-size-limit

Signed-off-by: youjiali1995 <c0aa3f5eb42bd3bf1adeeced4b718fc1900fde64@gmail.com>

* Apply suggestions from code review

* Update tidb-configuration-file.md

Co-authored-by: TomShawn <3d0966147538bc5ab020e8dffa2c0b746f9728a6@users.noreply.github.com>
pingcap/docs-cn,pingcap/docs-cn