chore: use unseq list

Author: liuruibin

CONTRIBUTING.md

@@ -2,8 +2,8 @@
 
 As a contributor, you should agree that:
 
-a. The producer can adjust the open-source agreement to be more strict or relaxed as deemed necessary.
-b. Your contributed code may be used for commercial purposes, including but not limited to its cloud business operations.
+- The producer can adjust the open-source agreement to be more strict or relaxed as deemed necessary.
+- Your contributed code may be used for commercial purposes, including but not limited to its cloud business operations.
 
 ## Create pull request
 PR are always welcome, even if they only contain small fixes like typos or a few lines of code. If there will be a significant effort, please document it as an issue and get a discussion going before starting to work on it.