Feat/3.0 upgrade guidelines

[siguangli]

Before submitting a new pull request, please make sure:

• Test cases have been added/updated/passed for the code you will submit.
• Documentation has added or updated.
• Commit message is following the Convention Commit guideline with maximum 72 characters.
• Squash the repeat code commits, short patches are welcome.

[hippy-service]

Hi, @siguangli. Thanks for your PR! 👏

🏷️ You can leave a comment in this PR with #help tag when you need help (e.g. some status checks run failed due to internal issue), admin team members will help asap.

[hippy-service]

🎉 It seems that this pull request has been approved by all required reviewers. But it has more than one normal commit, I will notify admin team member to merge it manually, please wait a moment.

• SHA: 5eb36e3

[hippy-actions]

⚠️ squash-merge action execution failed, because of pull request title does not meet the Convention Commit guideline.

Please check the following details:

⧗   input: Feat/3.0 upgrade guidelines
✖   subject may not be empty [subject-empty]
✖   type may not be empty [type-empty]
✖   header subject cannot be empty [function-rules/header-min-length]
✖   scope may not be empty [scope-empty]

✖   found 4 problems, 0 warnings
ⓘ   Get help: https://github.com/conventional-changelog/commitlint/#what-is-commitlint

@siguangli