ReadonlyactionOptional ReadonlydiscountOptional ReadonlysortNew value to set (between 0 and 1) that determines the order in which the CartDiscounts are applied; a CartDiscount with a higher value is prioritized.
Required if `discountGroup` is absent. If `discountGroup` is set, the CartDiscount will use the sort order of the DiscountGroup.
Reference to a DiscountGroup that the Cart Discount must belong to. If empty, any existing value will be removed.