解决 github项目clone报错 Failed connect to github.com:443; Connection

系统环境：CentOS Linux release 7.6.1810 (Core)  起因：npm构建时报错 npm ERR! Error while executing: npm ERR! /usr/bin/git ls-remote -h -t https://github.com/nhn/raphael.git npm ERR! npm ERR! fatal: unable to access 'https://github.com/nhn/raphael.git/': Failed connect to github.com:443; Connection timed out npm