yarn 下包的时候提示错误：There appears to be trouble with your network connection. Retrying
原因： yarn超时，终端多次提示There appears to be trouble with your network connection. Retrying
解决如下：
//查看代理 git config list //删除代理 git config delete registry //或者删除代理 git config delete proxy //更换淘宝镜像 yarn config set registry https://registry.npm.taobao.org
