Allow checking out the commits when reviewing

If possible, I like to review PRs commits by commit. I d like to be able to check out these commits one by one, see what has changed and be able to comment on it and be able to edit them and try out some suggestions before proposing them.

Current behavior:

• commenting on separate commits doesn't work, (already opened an issue for that)
• can not make changes to the files
• without checking them out I cant see typescript types on hover etc.

Propose behavior:

• allow checking out the commit
• this would allow the files to be edited and have all vs code features

首先检查扩展目前如何处理 pull request 提交的审查，以及为什么无法检出或编辑单个提交。当审查者可以检出单个提交、检查 TypeScript 功能（例如悬停信息）、编辑文件并在提出建议之前尝试这些建议时，即视为完成。