[Technical] How to use vendor from Order entity

[lucasferraro]

With the implementation of Business Account we've created the entity BusinessRestaurantGroup which holds all the restaurants that are included in the Platform Catering agreement. The idea with BusinessRestaurantGroup is that it has all the setup/configuration for all the restaurants to be applied for each order (fulfillment, delivery fees, etc.)

With that in mind then we changed the getVendor method in Order entity so that in case of a Business Account order we return the BusinessRestaurantGroup associated and with it, we could calculate delivery fees for example.

But then, we realized that getVendor method is also used to show information about the vendor of the Order like the name, the address, or even the ID to build the path to the vendor page. But for Business Account we face a problem because for configuration/setup information we want the BusinessRestaurantGroup data, but for name, ID, address, etc we want to have them from the Restaurant where the user/employee has made the order.

With that in mind, I've created this PR where now we can use a new method getSetupVendor to get the data related to setup/configuration and the existing getVendor method will keep its original implementation and should return the "real" vendor information, i.e. for Business Account it will return the restaurant.