[IMP] joint_buying_product: Add tracking on order amount. however, it…

… doesn't look to work for V12, but we hope it will work in V16. See: odoo/odoo#31301

joint_buying_product/models/joint_buying_purchase_order.py

@@ -175,6 +175,7 @@ class JointBuyingPurchaseOrder(models.Model):
     amount_untaxed = fields.Float(
         string="Total Untaxed Amount",
         compute="_compute_amount",
+        track_visibility=True,
         store=True,
         digits=dp.get_precision("Product Price"),
     )