Improve the README

## Do you have a favorite Git Resource?
Add it to the README!
If you need help, check out the Appendix in the training manual.

Open the repository README and review the Appendix in the training manual for guidance. Add a favorite Git resource to the README, keeping it consistent with the existing content. The work is done when the resource appears in the README.

由索引模型根据 Issue 内容生成。