Failed connect to github.com:443； Connection timed out

完美解决  git clone 报错问题

问题展示如下：

git clone https://github.com/xxx.git
Cloning into 'xxx'...
fatal: unable to access 'https://github.com/xxx.git/': Failed connect to github.com:443; Connection timed out

只需要在命令行中执行

git config --global --unset http.proxy 
git config --global --unset https.proxy