Fix setup-node action config

Author: nicolasfont

.github/workflows/ci.yml

@@ -7,9 +7,9 @@ jobs:
       - name: Checkout source code
         uses: actions/checkout@v2
       - name: Setup Node
-        uses: actions/setup-node@v1
+        uses: actions/setup-node@v2
         with:
-          node_version: 12.x
+          node-version: '12'
       - name: Install dependencies
         run: npm install
       - name: Run lerna bootstrap