remote: The project you were looking for could not be found

GitLab: The project you were looking for could not be found issue

问题描述：
项目存在，但是在提交时提示项目不存在。

问题原因：
不详。

解决办法：
将 https://gitlab.com/{gitlab_user}/project_repo.git 修改为 https://{gitlab_user}@gitlab.com/gitlab_user/project_repo.git 即可。即添加用户名。