Allow setting a status as closing even if the project has no close_status
When determining if a status "closes" tickets or not, we should first
check if it was set to and only if it wasn't then check if there was a
close_status set for it. Otherwise the logic wasn't correctly interpreted.
Fixes https://pagure.io/pagure/issue/4958
Signed-off-by: Pierre-Yves Chibon <pingou@pingoured.fr>