ci: use certain OS version instead of latest

[peaceiris]

• ci: Change macos-latest to macos-10.15
• ci: Change windows-latest to windows-2019
• ci: Add macos-11.0 (macOS Big Sur 11.0)
• docs: Add macos-11.0 (macOS Big Sur 11.0)
• ci: Add deploy step for macos-11.0 (macOS Big Sur 11.0)

https://docs.github.com/en/free-pro-team@latest/actions/reference/workflow-syntax-for-github-actions#jobsjob_idruns-on

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 61.17%. Comparing base (4c8cffc) to head (d94773c).
⚠️ Report is 431 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #530   +/-   ##
=======================================
  Coverage   61.17%   61.17%           
=======================================
  Files           4        4           
  Lines         273      273           
  Branches       48       48           
=======================================
  Hits          167      167           
  Misses        105      105           
  Partials        1        1           

☔ 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.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.