iOS设备在SDK3.8.1中，若设置了margins，则observe会失效【无法触发监听事件】

this.createIntersectionObserver().relativeToViewport({ top: 100, bottom: 100 })

https://developers.weixin.qq.com/miniprogram/dev/api/wxml/IntersectionObserver.relativeToViewport.htmlhttps://developers.weixin.qq.com/miniprogram/dev/api/wxml/IntersectionObserver.relativeToViewport.html