[FIX] website_sale: add to cart modal properly displayed on list view

Made the modal for add to cart to be the same when in Grid view and list
view. We achieve this by modifying the css inside
`#products_grid.o_wsale_layout_list`.

opw-3235969

closes odoo/odoo#133439

Signed-off-by: Antoine Vandevenne (anv) <anv@odoo.com>