* remote: ADD sock attribute and pass it to SSHConnection constructor
The sock attribute is set to a `paramiko.ProxyCommand` object
if 'ProxyCommand' exists in config to `None` other-wise
(which is the default option in `paramiko.client.SSHClient.connect()`).
FIXES#3560
* Move paramiko import to RemoteSSH __init__
* Update dvc/remote/ssh/__init__.py
* Update dvc/remote/ssh/__init__.py
* Update dvc/remote/ssh/__init__.py
* Update dvc/remote/ssh/__init__.py
Co-authored-by: Sergio Garcia <[email protected]>
Co-authored-by: Ruslan Kuprieiev <[email protected]>
