Force authenticate user

I don't think we should care about what authentication scheme the tests are using, because we are not testing the authentication scheme itself. This will also remove having the `raw_password` and `username` fields constraint on the user factory, and having to set the `use_token_auth` flag, and therefore make the package easier/more pleasant to use.
OK, that's the shit right there! I missed that addition. That is what I wanted to see all along :+1: