Smootify.selectVariant()
selects a variant (its number or gid) of a `smootify-product` of the page: the element, or one inside it; false when the product has no such variant
selects a variant (its number or gid) of a smootify-product of the page: the element, or one inside it; false when the product has no such variant New in 2.0.
selectVariant(product: HTMLElement, variantId: string | number): boolean