[FIX] point_of_sale: consider timezone in return orders

Similar to 21575407 for returns
payment_date is a date field, make sure the day is the one of the user

Closes #25342

addons/point_of_sale/models/pos_order.py

@@ -143,7 +143,7 @@ class PosOrder(models.Model):
                 cash_journal_id = cash_journal[0].id
             order.add_payment({
                 'amount': -pos_order['amount_return'],
-                'payment_date': fields.Datetime.now(),
+                'payment_date': fields.Date.context_today(self),
                 'payment_name': _('return'),
                 'journal': cash_journal_id,
             })