fix: bump stefanzweifel/git-auto-commit-action from 5 to 6

Bumps [stefanzweifel/git-auto-commit-action](https://github.com/stefanzweifel/git-auto-commit-action) from 5 to 6.
- [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@v5...v6)

---
updated-dependencies:
- dependency-name: stefanzweifel/git-auto-commit-action
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/client-generate.yml

@@ -60,7 +60,7 @@ jobs:
     - name: Generate README
       run: php .regen-docs.php
 
-    - uses: stefanzweifel/git-auto-commit-action@v5
+    - uses: stefanzweifel/git-auto-commit-action@v6
       with:
         commit_message: Apply php-cs-fixer changes