If a feature is activated or not depends on the database which is reset
after each test scenario. So enabling a feature doesn't leak into other
scenarios.
Just enabling the feature is less code and more realistic than mocking a
method call.
The authorize action is used for authorizing off-session payments where the order is *already complete* and the order cycle may have closed (backoffice and subscriptions). They are essentially asynchronous and not coupled to the current open/closed state of the order cycle.
