Update test.yml

Try node 20.x

Author: jdhameli

.github/workflows/test.yml

@@ -32,7 +32,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v4
         with:
-          "node-version": 18.x
+          "node-version": 20.x
       - name: npm clean install
         run: npm ci
       - name: Start Xvfb