This is a continuation of #2728, with a test case added.
Fixes#2633.
I kept @zareck 's commit as is, because I believe it is correct. We can't move the check to `owner.CanForkRepo()`, because `owner` is the future owner of the forked repo, and may be an organization. We need to check the admin permission of the `doer`, like in the case of repository creation.
I verified that the test fails without the `ForkRepository` change, and passes with it.
Co-authored-by: Cassio Zareck <cassiomilczareck@gmail.com>
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/3277
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: Gergely Nagy <forgejo@gergo.csillger.hu>
Co-committed-by: Gergely Nagy <forgejo@gergo.csillger.hu>