[FIX] sale_loyalty: check coupon partner

Steps to reproduce:
    - create a "gift card" with a specific customer;
    - use gift card code with any customer (Sales and/or eCommerce app).

Issue:
    The coupon is validated.

Cause:
    There is no partner verification when applying a coupon.

opw-3027251

closes odoo/odoo#103673

X-original-commit: 092d652b1f38b804657b6e1d383a157615cf9487
Signed-off-by: Grazioso Andrea (agr) <agr@odoo.com>
Signed-off-by: Lefebvre Thomas (thle) <thle@odoo.com>

addons/sale_loyalty/i18n/sale_loyalty.pot

@@ -182,6 +182,12 @@ msgstr ""
 msgid "ID"
 msgstr ""
 
+#. module: sale_loyalty
+#: code:addons/sale_loyalty/models/sale_order.py:0
+#, python-format
+msgid "Invalid partner."
+msgstr ""
+
 #. module: sale_loyalty
 #: code:addons/sale_loyalty/models/sale_order.py:0
 #, python-format

addons/sale_loyalty/models/sale_order.py

@@ -947,6 +947,8 @@ class SaleOrder(models.Model):
                 not coupon.program_id.reward_ids or\
                 not coupon.program_id.filtered_domain(self._get_program_domain()):
                 return {'error': _('This code is invalid (%s).', code), 'not_found': True}
+            elif coupon.partner_id and coupon.partner_id != self.partner_id:
+                return {'error': _('Invalid partner.')}
             elif coupon.expiration_date and coupon.expiration_date < fields.Date.today():
                 return {'error': _('This coupon is expired.')}
             elif coupon.points < min(coupon.program_id.reward_ids.mapped('required_points')):