chore: Add .git-blame-ignore-revs to ignore style in blame view

[matthewfeickert]

Add a git blame ignore-revs file to automatically ignore commits listed in it from the blame view on GitHub. Include in it style changes added by pre-commit hooks which touch multiple files.

To ignore the commits in the .git-blame-ignore-revs when running git blame locally run: git blame --ignore-revs-file .git-blame-ignore-revs.

c.f.:

• https://git-scm.com/docs/git-blame#Documentation/git-blame.txt---ignore-revs-fileltfilegt
• https://docs.github.com/en/repositories/working-with-files/using-files/viewing-a-file#ignore-commits-in-the-blame-view