Upgrade `setup-node` to fix CI failure

https://github.com/actions/setup-node/issues/1275#issuecomment-278820408

.github/workflows/karma-tests.yml

@@ -22,9 +22,9 @@ jobs:
         # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Use Node.js ${{ matrix.node-version }}
-      uses: actions/setup-node@v2
+      uses: actions/setup-node@v4
       with:
         node-version: ${{ matrix.node-version }}
         cache: 'npm'