function convertToLineItems(items) {
  return items.reduce((res, { sku, quantity }) => {
    const variant = data.variants.find(p => p.sku === sku);
    if (variant) {
      res.push({ ...variant, quantity, total: variant.price * quantity });
    }
    return res;
  }, []);
}
Converts cookie line items to cart line items.
@param {CookieLineItem[]} items - List of cookie line items.
@returns {LineItem[]} - Cart line items.