Move vehicle-status to Connect and start unit tests

[dvx76]

Small PR to:

1. Move vehicle-status from the Skoda/Technical to the Connect platform, as discussed on Discord. The endpoint requires the scopes available in the Connect client.
2. Start unit tests. We're probably going to be refactoring this new code quite a bit so I'd love to have some unit tests around the principal external methods. Don't want to test everything manually all the time + everyone can typically only test things for 1 car, at best. This starts with just one pytest-based unit test which tests a successful sign in through the Connect.auth() method. All API responses are mocked using aioresponses. Needs to be tidied up some more and obviously extended, but it's a starting point.

$  pytest test/test_connect.py
.                                     [100%]
1 passed

I'm not very familiar with CI jobs in Github... @WebSpider is this something we could have executed for each PR through Github actions? Could you help set that up?