This property getter must be called with the PerformanceResourceTiming object as the receiver.
PerformanceResourceTiming
新增于: v18.2.0, v16.17.0
高分辨率毫秒时间戳，表示 Node.js 在开始建立与服务器的连接以获取资源之前的时间。
【The high resolution millisecond timestamp representing the time immediately before Node.js starts to establish the connection to the server to retrieve the resource.】