Update README.md

README.md

@@ -95,6 +95,15 @@ mysql -u root -h 127.0.0.1 -P 4000
 
 Since Jun 2022, we start using [github classroom](https://github.com/talent-plan/tinysql/blob/course/classroom.md) to accept labs and provide autograding timely. The github classroom invitation is https://classroom.github.com/a/cdlNNrFU. The discussion Wechat/Slack group and the certification after you pass the class is provided in the [tinyKV learning class](https://talentplan.edu.pingcap.com/catalog/info/id:263)
 
+
+Autograding is a workflow which can automatically run test cases and give feedback timely. However there are some limitations in Github classroom, in order to make golang work and run it in our self-hosted machines, **you need to overwrite the workflow generated by Github classroom and commit it**.
+
+```sh
+cp scripts/classroom.yml .github/workflows/classroom.yml
+git add .github
+git commit -m"update github classroom workflow"
+```
+
 ## Contributing
 
 Any feedback and contribution is greatly appreciated. Please see [issues](https://github.com/tidb-incubator/tinykv/issues) if you want to join in the development.