[FIX] point_of_sale: restore payment method in invoice

Accounting moved the logic of _get_reconciled_vals
into _compute_payments_widget_reconciled_info but did not made the
change in point_of_sale.
This commit resolve this by putting the logic of the previous
_get_reconciled_vals into an override of the
_compute_payments_widget_reconciled_info method.
This is done because this is a legal requirement in France to have and
maybe in other countries.

closes odoo/odoo#133655

Signed-off-by: Robin Heinz (rhe) <rhe@odoo.com>

addons/point_of_sale/models/account_move.py

@@ -43,13 +43,19 @@ class AccountMove(models.Model):
 
         return lot_values
 
-    def _get_reconciled_vals(self, partial, amount, counterpart_line):
+    def _compute_payments_widget_reconciled_info(self):
         """Add pos_payment_name field in the reconciled vals to be able to show the payment method in the invoice."""
-        result = super()._get_reconciled_vals(partial, amount, counterpart_line)
-        if counterpart_line.move_id.sudo().pos_payment_ids:
-            pos_payment = counterpart_line.move_id.sudo().pos_payment_ids
-            result['pos_payment_name'] = pos_payment.payment_method_id.name
-        return result
+        super()._compute_payments_widget_reconciled_info()
+        for move in self:
+            if move.invoice_payments_widget:
+                if move.state == 'posted' and move.is_invoice(include_receipts=True):
+                    reconciled_partials = move._get_all_reconciled_invoice_partials()
+                    for i, reconciled_partial in enumerate(reconciled_partials):
+                        counterpart_line = reconciled_partial['aml']
+                        pos_payment = counterpart_line.move_id.sudo().pos_payment_ids
+                        move.invoice_payments_widget['content'][i].update({
+                            'pos_payment_name': pos_payment.payment_method_id.name,
+                        })
 
 class AccountMoveLine(models.Model):
     _inherit = 'account.move.line'