Fix user.* git-config example

See https://github.com/orgs/community/discussions/26560.

README.md

@@ -217,8 +217,8 @@ jobs:
       - uses: actions/checkout@v3
       - run: |
           date > generated.txt
-          git config user.name github-actions
-          git config user.email github-actions@github.com
+          git config user.name 'github-actions[bot]'
+          git config user.email '41898282+github-actions[bot]@users.noreply.github.com'
           git add .
           git commit -m "generated"
           git push