It is a part of the Phabricator to Gitea migration.
The issue template is based on the bug submission instructions which
are shown in the Phabricator's bug submission form. Some further tweaks
are likely needed, but the current version of the template simplifies
re-iteration while working on the migration.
The pull request template is needed to override the template in the
.github folder which is otherwise picked up by Gitea.