github 默认开源声明,
https://docs.github.com/en/github/site-policy/github-terms-of-service#5-license-grant-to-other-users5. License Grant to Other Users
Any User-Generated Content you post publicly, including issues, comments, and contributions to other Users' repositories, may be viewed by others. By setting your repositories to be viewed publicly, you agree to allow others to view and "fork" your repositories (this means that others may make their own copies of Content from your repositories in repositories they control).
这句话就至少是允许修改使用的,只要不发行,
this means that others may make their own copies of Content from your repositories in repositories they control