Bump stefanzweifel/git-auto-commit-action from 4 to 7

Bumps [stefanzweifel/git-auto-commit-action](https://github.com/stefanzweifel/git-auto-commit-action) from 4 to 7.
- [Release notes](https://github.com/stefanzweifel/git-auto-commit-action/releases)
- [Changelog](https://github.com/stefanzweifel/git-auto-commit-action/blob/master/CHANGELOG.md)
- [Commits](stefanzweifel/git-auto-commit-action@v4...v7)

---
updated-dependencies:
- dependency-name: stefanzweifel/git-auto-commit-action
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/render-rmarkdown.yaml

@@ -32,6 +32,6 @@ jobs:
         run:  Rscript -e 'rmarkdown::render("README.Rmd")'
 
       - name: Commit the results
-        uses: stefanzweifel/git-auto-commit-action@v4
+        uses: stefanzweifel/git-auto-commit-action@v7
         with:
           commit_message: Render `README.md` after changes to the `.Rmd` version (GitHub action)