Creates an idle interval in a [SceneTreeTween] animation. [IntervalTweener] is used to make delays in a tweening sequence. See [method SceneTreeTween.tween_interval] for more usage information. [b]Note:[/b] [method SceneTreeTween.tween_interval] is the only correct way to create [IntervalTweener]. Any [IntervalTweener] created manually will not function correctly.