possible fix for double event registration in child models when calling events from parent trait use

[solis-eduardo]

Came across this issue when using owen-it/laravel-auditing.
My Model class uses the Auditable trait, but the events are registered twice because parentIsBooting only accounts for traits used by the parent class itself, to solve this problem I created a static array for parent classes and added an alternative isset verification, similar to the preexisting $parentBootMethods logic.

[solis-eduardo]

Forgot to mention: it can be bypassed by declaring a empty boot method, like so:

    public static function boot() {
        parent::boot();
    }