[FIX] website_sale_stock: prevent buying consumable

- In Website > Settings, set 'Show inventory on website and prevent
  sales if not enough stock'
- Create a consumable product P, publish on the eCommerce
- As user 1, buy 1 units of P => validate the SO => 1 unit is reserved
- As user 2, add 1 unit of P to the cart. In the cart click on the `+`
  to add a unit

The product is removed from the cart.

This happens because `virtual_available` quantity is taken into account,
while it shouldn't be since it is a consumable.

opw-2245075

closes odoo/odoo#50401

Signed-off-by: Nicolas Martinelli (nim) <nim@odoo.com>

addons/website_sale_stock/views/website_sale_stock_templates.xml

@@ -9,7 +9,7 @@
     <!-- Shopping Cart Lines -->
     <template id="website_sale_stock_cart_lines" inherit_id="website_sale.cart_lines" name="Shopping Cart Lines">
         <xpath expr="//input[@type='text'][hasclass('quantity')]" position="attributes">
-          <attribute name='t-att-data-max'>(line.product_uom_qty + (line.product_id.virtual_available - line.product_id.cart_qty)) if line.product_id.inventory_availability in ['always', 'threshold'] else None</attribute>
+          <attribute name='t-att-data-max'>(line.product_uom_qty + (line.product_id.virtual_available - line.product_id.cart_qty)) if line.product_id.type == 'product' and line.product_id.inventory_availability in ['always', 'threshold'] else None</attribute>
         </xpath>
         <xpath expr="//div[hasclass('css_quantity')]//i[hasclass('fa-plus')]/.." position="replace">
           <t t-if="line._get_stock_warning(clear=False)">