新增于: v16.17.0
表示 Node.js 接收到资源的最后一个字节之后或传输连接关闭之前的时间（以先到者为准）的高解析度毫秒时间戳。
Added in: v16.17.0
The high resolution millisecond timestamp representing the time immediately
after Node.js receives the last byte of the resource or immediately before
the transport connection is closed, whichever comes first.