products_relation is now split in two, products_relation and
products_relation_incl_supplier_properties.
It avoids using a flag argument which is not a a good practice see:
https://martinfowler.com/bliki/FlagArgument.html
Due to primary_taxon and supplier having moved to the variant, filtering
by_producer and by_category with a custom order involves some
complicated sql queries. So we moved the sorting logic from
ProductsRenderer to OrderCycles::DistributedProductsService so we can
keep the complicated SQL logic contained in one place
