[FIX] account: false complete_tax_set tax default

When setting a chart of account on a company, we have default taxes from
the default chart of account different from chosen one.

But if a chart of account is chosen, it should override them in the
onchange_chart_template_id function. This works as expected for a
truthy complete_tax_set chart of account template, but not for a falsy
complete_tax_set chart of account template.

The complete_tax_set indicates that we don't want to set default taxes
and the user should do it or modify the given tax rates himself.

opw-1824751
closes #23655

addons/account/models/chart_template.py

@@ -740,6 +740,9 @@ class WizardMultiChartsAccounts(models.TransientModel):
                 res.setdefault('domain', {})
                 res['domain']['sale_tax_id'] = repr(sale_tax_domain)
                 res['domain']['purchase_tax_id'] = repr(purchase_tax_domain)
+            else:
+                self.sale_tax_id = False
+                self.purchase_tax_id = False
             if self.chart_template_id.transfer_account_id:
                 self.transfer_account_id = self.chart_template_id.transfer_account_id.id
             if self.chart_template_id.code_digits: