DOC use pull request builds of readthedocs for doc build check

[MatthewSZhang]

Checklist

• Used a personal fork to propose changes
• A reference to a related issue: DOC builds check issue of readthedocs #92
• A description of the changes: remove long-lived branches, e.g. 0.3.X and 0.4.X, for doc build check

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (84b2f83) to head (a301482).
Report is 29 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #93   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            6         6           
  Lines          603       609    +6     
=========================================
+ Hits           603       609    +6     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.