- update to 1.21.8-0:
* Fix /api/v1/{owner}/{repo}/issue_templates which was always failing with a
500 error.
* Prevent error 500 on /user/settings/security when SignedUser has a linked
account from a deactivated authentication source.
* Fix error 500 when pushing release to an empty repo.
* Fix incorrect rendering csv file when file size is larger than UI.CSV.MaxFileSize.
* Fix error 500 when deleting account with incorrect password or unsupported login type.
* handle user-defined name anchors like [Link](#link) linking to Link.
* Use correct head commit for CODEOWNER.
* Fix manual merge button.
* Make meilisearch do exact search for issues.
* Fix PR creation via api between branches of same repo with head field namespaced.