Before the Shop::OrderCyclesList service would return order cycles even if they are not ready for checkout and we had a check before calling the service in BaseController which would return OrderCycle.where('false'). It seems like this check should be part of the service too.
The method `associate_customer` only loads a customer but doesn't
actually associate one. So the deleted line doesn't have any effect.
The intention was to reset the customer after switching shops but the
before_validation logic on the order model takes care of that already.
I'm renaming this private method here for clarity.
