[9.x] Add forceDeleting event

[xurshudyan]

Before

    public static function booted()
    {
        static::deleting(function (User $user) {
            if ($user->isForceDeleting()) {
                //
            }
        });
    }

After

  public static function booted()
  {
      static::forceDeleting(function (User $user) {
          // do something
      });
  }