Update node version used for bundle preview workflow (#86)

Author: mlr

.github/workflows/deploy-bundle-preview.yml

@@ -22,9 +22,9 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Setup Node.js
-        uses: actions/setup-node@v3
+        uses: actions/setup-node@v4
         with:
-          node-version: 16.20.2
+          node-version: 21.6.1
 
       - name: Install Dependencies
         run: npm ci