[FIX] account_ux: error al ingresar en ajustes de contabilidad

Ticket: 68143
Réplica del error en runbot de adhoc 17:
https://drive.google.com/file/d/1k5FdLMvFryGKuNBoJnK5RMim3mZPqv6s/view

closes #469

Signed-off-by: Katherine Zaoral <kz@adhoc.com.ar>

account_ux/wizards/res_config_settings.py

@@ -32,9 +32,9 @@ def _compute_tax_ids(self):
         for rec in self:
             company_id = rec.company_id.id
 
-            taxes_ids = ir_default.get('product.template', 'taxes_id', company_id=company_id) or \
+            taxes_ids = ir_default._get('product.template', 'taxes_id', company_id=company_id) or \
                 rec.company_id.account_sale_tax_id.ids
-            supplier_taxes_ids = ir_default.get('product.template', 'supplier_taxes_id', company_id=company_id) or \
+            supplier_taxes_ids = ir_default._get('product.template', 'supplier_taxes_id', company_id=company_id) or \
                 rec.company_id.account_purchase_tax_id.ids
 
             rec.sale_tax_ids = taxes_ids