Update actions/checkout action to v4

Author: renovate[bot]

.github/workflows/nodejs.yml

@@ -12,7 +12,7 @@ jobs:
         node-version: [12.x, 14.x, 16.x]
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Use Node.js ${{ matrix.node-version }}
       uses: actions/setup-node@v2
       with: