post https://demo-smartcharging.jedlix.com/api/v1/users//connect-vehicle
This endpoint allows a user to connect a test vehicle to their account in the QA environment.
If the user does not have any existing vehicles, a new test vehicle will be created and connected to their account.
Note: This endpoint is only available in the QA environment and works only for test vehicles. For connecting vehicles of other brands,
please use the Jedlix Connect interface.