这很可能是域名解析的问题

因此，直接为域名配IP、修改host能解决问题。

Linux用户修改  /etc/hosts
cd /etc #进入目录
vi hosts #编辑hosts文件
粘贴下面的配置即可


windows用户修改  C:\WINDOWS\system32\drivers\etc\hosts

加入以下在配置

# GitHub hosts
52.74.223.119      github.com
203.98.7.65        gist.github.com
151.101.184.133    assets-cdn.github.com
151.101.184.133    raw.githubusercontent.com
151.101.184.133    gist.githubusercontent.com
151.101.184.133    cloud.githubusercontent.com
151.101.184.133    camo.githubusercontent.com
151.101.184.133    avatars0.githubusercontent.com
151.101.184.133    avatars1.githubusercontent.com
151.101.184.133    avatars2.githubusercontent.com
151.101.184.133    avatars3.githubusercontent.com
151.101.184.133    avatars4.githubusercontent.com
151.101.184.133    avatars5.githubusercontent.com
151.101.184.133    avatars6.githubusercontent.com
151.101.184.133    avatars7.githubusercontent.com
151.101.184.133    avatars8.githubusercontent.com
151.101.185.194    github.global.ssl.fastly.net