This lib is designed to include ESPAsyncWebSrv, because there just have ESPAsyncWebSrv on Arduino, some other libs may still use the old one, so they need to to be inluded by this lib.
本库文件仅仅是将ESPAsyncWebServer指向了存在于Arfuino中的ESPAsyncWebSrv，方便使用ESPAsyncWebServer库的程序调用ESPAsyncWebServ，并没有别的功能；