chore(deps): update actions/setup-node action to v6

Author: renovate[bot]

.github/workflows/sync-docs-from-node.yml

@@ -239,7 +239,7 @@ jobs:
           token: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Setup Node.js
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: '20'
           cache: 'npm'