[FIX] delivery: fix bad Exception handling

When get_price() is called during tests, a ValidationError was returned but not catched
correctly due to the unavailability of delivery service.
Because this method is called during the creation of new sale order, it leads to some
operational error (broken cursor).

addons/delivery/models/delivery_carrier.py

@@ -120,7 +120,7 @@ class DeliveryCarrier(models.Model):
                 try:
                     computed_price = self.get_shipping_price_from_so(order)[0]
                     self.available = True
-                except UserError as e:
+                except ValidationError as e:
                     # No suitable delivery method found, probably configuration error
                     _logger.info("Carrier %s: %s, not found", self.name, e.name)
                     computed_price = 0.0