Fixes #28853
Needs both https://gitea.com/gitea/act_runner/pulls/473 and
https://gitea.com/gitea/act_runner/pulls/471 on the runner side and
patched `actions/upload-artifact@v4` / `actions/download-artifact@v4`,
like `christopherhx/gitea-upload-artifact@v4` and
`christopherhx/gitea-download-artifact@v4`, to not return errors due to
GHES not beeing supported yet.
(cherry picked from commit a53d268aca87a281aadc2246541f8749eddcebed)