Delete file after download

OrdinaryCarsController.php

```php
header('Content-Description: File Transfer');
        header('Content-Type: application/octet-stream');
        header('Content-Disposition: attachment; filename=' . $zip['name']);
        header('Content-Transfer-Encoding: binary');
        header('Connection: Keep-Alive');
        header('Expires: 0');
        header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
        header('Pragma: public');
        //header('Content-Length: ' . $size);
        readfile($zip['path']);

        $file = new \Cake\Filesystem\File($zip['path']);
        $file->delete();
        exit();
```