fix

.github/workflows/sync-howto-docs.yml

@@ -21,7 +21,7 @@ jobs:
           TARGET_BRANCH: 'test-howto-sync'
           ACCESS_TOKEN: ${{ secrets.REPO_ACCESS_TOKEN_GU }}
         run: |
-          CHANGED_FILES=$(git diff --name-only --diff-filter=AMDR ${{ github.ref }} | grep -e 'howto-.*\.md$' || true)
+          CHANGED_FILES=$(git diff --name-only --diff-filter=AMDR ${{ github.event.before }} | grep -e 'howto-.*\.md$' || true)
 
           if [ -z "$CHANGED_FILES" ]; then
             echo "No new how-to file changes to sync"