Add Node.js setup step in copilot-test-tools workflow

Author: austenstone

.github/workflows/copilot-test-tools.yml

@@ -9,6 +9,10 @@ jobs:
       cancel-in-progress: true
     steps:
       - uses: actions/checkout@v5
+      - name: Setup Node 22
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
       - run: npm install -g @github/copilot
       - run: |
           mkdir -p ~/.copilot