scheduled workflows: fix branch, add new files.

[MikeMcQuaid]

• ensure we reset to origin/master so we only have the commit we care
  about in the PR
• ensure we git add to include any new files
• don't use git commit -a and instead rely only on files added with git add

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• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew tests with your changes locally?

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[MikeMcQuaid]

#8423 was created from this and looks totally correct now @vidusheeamoli, @issyl0, @mistydemeo 🎉