adding 'filter_on_archive' function to shopping_client
adding 'filter_on_archive' function to shopping_client. This filters out all the items that do not belong to the provided connectors.
This functionality is also in the 'validate_basket_item' of the (zooniverse) connector, but that function is only called when 'convert_to_pandas = true', which is not always the case. So this 'filter_on_archive' splits up the 'validation' and the 'filtering.