Submitting the repo avatar form without selecting a file shows a raw Go error: `Avatar.Open: open : no such file or directory.`. The existing `nil` check does not prevent this from happening.
The user avatar handler already guards against this same problem with [`form.Avatar != nil && form.Avatar.Filename != ""`](e1cecbd276/routers/web/user/setting/profile.go (L141)), I've done the same for the repo avatar handler.
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/11335
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: Bram Hagens <bram@bramh.me>
Co-committed-by: Bram Hagens <bram@bramh.me>