Update node to v 18.x for CI

Author: prushforth

.github/workflows/ci-testing.yml

@@ -12,7 +12,7 @@ jobs:
       - name: Use Node.js
         uses: actions/setup-node@v1
         with:
-          node-version: '16.x'
+          node-version: '18.x'
       - run: sudo apt-get install xvfb
       - run: npm install
       - run: npx playwright install