Git在push推送时，报错提示信息如下：
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.
原因：本地和远程仓库代码不同步，因此需要先pull，进行合并然后再进行push
git pull --rebase origin master
git push -u origin master