Flysystem write() is expecting an empty array

[cgsmith]

https://github.com/thephpleague/flysystem-sftp/blob/2.x/SftpAdapter.php#L122

The $config should be an empty array to keep consistent with API. Currently if you use the SFTP Adapter it requires the Config object to be passed down.

The code will cause an error but only for SFTP Adapter