Add support for searching by productId on productList loader

[ingridflack]

Description

This PR aims to add support for searching by productId on the productList loader by adding 2 new props while keeping backward compatibility with the ids prop.

Changes

• Add skus and productIds props that will have the data for each type of search
• The ids prop fallbacks to the same behavior as skus to be backward compatible
• Add a helper function to avoid code duplication

Test instructions

• Test using ids or skus, should return a list of skus;
• Test using productIds should return a list of products;
• Other behaviors should stay the same.