text: Title: Configuring ranges does not allow excluding products through the UI
  Body: The range model allows exclusion of specific products:
  https://github.com/django-oscar/django-oscar/blob/151dc05395865ec0f51cdd45be9970a1bbea2f0c/src/oscar/apps/offer/abstract_models.py#L854
  
  However, you can not configure those through the dashboard UI, while it's a pretty useful feature.
  
  You can configure single included products, with the "Save and edit products" button;
  <img width="349" alt="image" src="https://user-images.githubusercontent.com/7702200/220860699-86ca45f9-8e73-4648-b978-8a4b242c7708.png">
  
  We could also allow users to exclude products in this view, though we would probably need to make the view UI a bit clearer here, as to me it already looks a bit clumsy.
  
  A separate view would do as well, but it should inherit the logic from the edit products view, as the only difference should be that it saves the products in the `excluded_products` field rather than the `included_products` field