컬렉션뷰 최상단으로 이동하기

@objc func scrollToTop(_ sender: UIButton) {
    collectionView.scrollToItem(at: IndexPath(row: 0, section: 0), at: .top, animated: true)
	// collectionView.scrollToItem(at: IndexPath(item: 0, section: 0), at: .top, animated: true)
}