Provide a customer group resolver service

An order could potentially belong to multiple groups for different reasons. However, it should always be placed on behalf of one group only with that group being the customer of the order. Different applications/modules building on top of Commerce Group may provide different group types that will function as the customer group for orders and, in complex settings, there could be more than one group type that functions as customer groups.

In order to provide a mechanism that is agnostic of the provider of the customer group type, we need a chain resolution service that allows the providers to resolve which of the groups that the order belongs to is its actual customer group.

This is useful, for example, for determining which customer group the order belongs to so that we can copy its profiles to the group's address book.