[FIX] account: wrongly defined fiscal pos constraint

Wrong usage of self in for loop

closes odoo/odoo#55334

X-original-commit: 5a0b06ab0447f2b09e71934f2cc3209e6ebe9359
Signed-off-by: Victor Feyens (vfe) <vfe@odoo.com>

addons/account/models/partner.py

@@ -48,7 +48,7 @@ class AccountFiscalPosition(models.Model):
     @api.constrains('zip_from', 'zip_to')
     def _check_zip(self):
         for position in self:
-            if self.zip_from and self.zip_to and position.zip_from > position.zip_to:
+            if position.zip_from and position.zip_to and position.zip_from > position.zip_to:
                 raise ValidationError(_('Invalid "Zip Range", please configure it properly.'))
 
     def map_tax(self, taxes, product=None, partner=None):