[13.x] Add static setter for authorizationServerResponseType

[RSpeekenbrink]

This PR adds a static setter for $authorizationServerResponseType in Passport.php to match other setters like useDeviceCodeModel().

This makes it more readable when wanting to override the default ResponseType, because it is in line with other setters.. i.e.;

$responseType = new BearerTokenResponseWithExtras();

// Only way currently
Passport::$authorizationServerResponseType = $responseType;

// New way
Passport::useAuthorizationServerResponseType($responseType);

This also makes it clearer that the ResponseType actually can be set and 'overwritten'.