Error in Composer scripts

[igaponov]

Script Yiinitializr\Composer\Callback::postPackageUpdate handling the post-package-update event terminated with an exception
[ErrorException]
Argument 1 passed to Yiinitializr\Composer\Callback::postPackageUpdate() must be an instance of Composer\Script\Event, instance of Composer\Script\PackageEvent given

[zeevin]

remove all the" $event" param type hint .
e.g.:public static function postUpdate( Event $event) to public static function postUpdate($event)