Add development guide about database changes (!577) · 合并请求 · gitlab-cn / GitLab · 极狐GitLab

Baodong请求将doc/database_changes_guidelines合并到main-jh 6月 07, 2022

Closes #1174 (closed)

This doc is translated from https://gitlab.com/gitlab-com/www-gitlab-com/-/raw/master/sites/handbook/source/handbook/ceo/chief-of-staff-team/jihu-support/jihu-database-change-process.html.md with some sentences adjusted.