Fix EZP-22027 location/url alias SPI cache not updated.

JIRA: https://jira.ez.no/browse/EZP-22027

Modifications to custom url alias in the administration interface should trigger a ```content/cache``` event, even if ObjectViewCache does not need to be cleared.

See also https://github.com/ezsystems/ezpublish-kernel/pull/677 for PR implementing 'content/location/cache' event listener