Fix all_products_except to exclude unavailable products

[rafaelmerlotto]

The all_products_except(product_ids) method in the TaxonCustomQueries module was returning products with available_on set to nil. This caused products that are not yet available to show in "You May Also Like" section on the product page.

Solution:
Updated the method to exclude products with available_on = nil

[jarednorman]

I think we should use the available scope.

[rafaelmerlotto]

Thanks for the feedback.

Using available scope is definitely cleaner. I've updated the PR to use:
all_products.available.where.not(id: products_ids)

This ensures the method returns only true available products in the section You May Also Like.