chore(deps): update stefanzweifel/git-auto-commit-action action to v6

Author: renovate[bot]

.github/workflows/publish-theme.yaml

@@ -98,7 +98,7 @@ jobs:
                     npm show $PACKAGE_NAME@$PACKAGE_VER # fails if the package is not available, succeeds if it is
 
             -   name: Commit the new theme version
-                uses: stefanzweifel/git-auto-commit-action@v5
+                uses: stefanzweifel/git-auto-commit-action@v6
                 with:
                     commit_message: 'chore: publish new version of @apify/docs-theme [skip ci]'
                     file_pattern: 'apify-docs-theme/package*.json'