Update files to support main branch in order to remove oppressive language

[chao2zhang]

Renaming branch is mostly automated. This PR hopefully should address most required manual changes in addition to https://github.com/github/renaming

Renaming a branch will:
- Re-target any open pull requests
- Update any draft releases based on the branch
- Move any branch protection rules that explicitly reference the old name
- Update the branch used to build GitHub Pages, if applicable
- Show a notice to repository contributors, maintainers, and admins on the repository homepage with instructions to update local copies of the repository
-  Show a notice to contributors who git push to the old branch
-  Redirect web requests for the old branch name to the new branch name
-  Return a "Moved Permanently" response in API requests for the old branch name

[codecov]

Codecov Report

Merging #3586 (4d0ce26) into master (091dc91) will not change coverage.
The diff coverage is n/a.

❗ Current head 4d0ce26 differs from pull request most recent head 2c08ee9. Consider uploading reports for the commit 2c08ee9 to get more accurate results

@@            Coverage Diff            @@
##             master    #3586   +/-   ##
=========================================
  Coverage     77.53%   77.53%           
  Complexity     2835     2835           
=========================================
  Files           464      464           
  Lines          8779     8779           
  Branches       1720     1720           
=========================================
  Hits           6807     6807           
  Misses         1046     1046           
  Partials        926      926           

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