Let acting on the status potentially set the close_status and vice versa
This way, making a closed ticket 'Open' will reset its close_status and
giving a 'close_status' to an open ticket will close it.
Fixes https://pagure.io/pagure/issue/2358
Fixes https://pagure.io/pagure/issue/2192
Signed-off-by: Pierre-Yves Chibon <pingou@pingoured.fr>