Added quick creation of promotions for products based on the "Wholesale price".

Added quick creation of promotions for products based on the "Wholesale price". This function allows you to transfer the “wholesale price” to the “Price” of the product and add the previous price value to the “Old price” item. You can set an action after the end of the promotion, for example, return the “Old price” to “Price”, and remove the “Promotion” mark. This way you can quickly launch promotions for a large number of products.