Partial fix for https://github.com/go-gitea/gitea/issues/17642. Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
This PR adds [GitBucket](https://gitbucket.github.io/) as migration source. Supported: - Milestones - Issues - Pull Requests - Comments - Reviews - Labels There is no public usable instance so no integration tests added.