Tracking issue of CI Refactor

[Xuanwo]

This is the tracking issue of CI Refactor

Proposal: #3415

Checklist

• ci: Refactor the whole ci into stages #3344
• Add docs on how our CI works and how to maintain it
• Build on x86_64 looks much slower than other platform?

[Xuanwo]

The refactoring has been done. We will continue work on #3611