解决方法：修改C:\WINDOWS\system32\drivers\etc\hosts文件，添加如下代码：
192.30.253.112 Build software better, together
192.30.253.119 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
140.82.112.4 github.com
151.101.185.194 github.global.ssl.fastly.net
203.98.7.65 gist.github.com
13.229.189.0 codeload.github.com
185.199.109.153 desktop.github.com
185.199.108.153 guides.github.com
185.199.108.153 blog.github.com
18.204.240.114 status.github.com
185.199.108.153 developer.github.com
185.199.108.153 services.github.com
192.30.253.175 enterprise.github.com
34.195.49.195 education.github.com
185.199.108.153 pages.github.com
34.196.237.103 classroom.github.com
