[IMP] delivery: add product_template.country_of_origin field

The origin of goods is required for the commercial invoice generation with
delivery providers. Until then we were using the warehouse country, but the
origin of goods is a different kind of field, as explained in this link:
[https://ec.europa.eu/taxation_customs/customs-4/international-affairs/origin-goods_en]( https://ec.europa.eu/taxation_customs/customs-4/international-affairs/origin-goods_en)

This commit is part of more important upcoming changes brought in Odoo
enterprise, especially with Fedex, Easypost, DHL and UPS commercial
invoices.

task-2701428

closes odoo/odoo#80900

Signed-off-by: Arnold Moyaux <arm@odoo.com>

addons/delivery/models/product_template.py

@@ -11,3 +11,9 @@ class ProductTemplate(models.Model):
         string="HS Code",
         help="Standardized code for international shipping and goods declaration. At the moment, only used for the FedEx shipping provider.",
     )
+    country_of_origin = fields.Many2one(
+        'res.country',
+        'Origin of Goods',
+        help="Rules of origin determine where goods originate, i.e. not where they have been shipped from, but where they have been produced or manufactured.\n"
+             "As such, the ‘origin’ is the 'economic nationality' of goods traded in commerce.",
+    )

addons/delivery/views/product_template_view.xml

@@ -8,6 +8,7 @@
     <field name="arch" type="xml">
 	       <xpath expr="//group[@name='group_lots_and_weight']" position="inside">
             <field name="hs_code"/>
+            <field name="country_of_origin"/>
         </xpath>
     </field>
 </record>