Improve example workflow to delete cache entries for closed PRs (#27618)

Co-authored-by: Sarah Edwards <[email protected]>

content/actions/using-workflows/caching-dependencies-to-speed-up-workflows.md

@@ -344,17 +344,11 @@ on:
 jobs:
   cleanup:
     runs-on: ubuntu-latest
-    steps:
-      - name: Check out code
-        uses: {% data reusables.actions.action-checkout %}
-        
+    steps:      
       - name: Cleanup
         run: |
           gh extension install actions/gh-actions-cache
           
-          REPO={% raw %}${{ github.repository }}{% endraw %}
-          BRANCH="refs/pull/{% raw %}${{ github.event.pull_request.number }}{% endraw %}/merge"
-
           echo "Fetching list of cache key"
           cacheKeysForPR=$(gh actions-cache list -R $REPO -B $BRANCH -L 100 | cut -f 1 )
 
@@ -368,6 +362,8 @@ jobs:
           echo "Done"
         env:
           GH_TOKEN: {% raw %}${{ secrets.GITHUB_TOKEN }}{% endraw %}
+          REPO: {% raw %}${{ github.repository }}{% endraw %}
+          BRANCH: refs/pull/{% raw %}${{ github.event.pull_request.number }}{% endraw %}/merge
 ```
 
 Alternatively, you can use the API to automatically list or delete all caches on your own cadence. For more information, see "[AUTOTITLE](/rest/actions/cache#about-the-cache-in-github-actions)."