Update actions/setup-node action to v2 (#31)

Co-authored-by: Renovate Bot <[email protected]>

Author: renovate[bot]

.github/workflows/build.yml

@@ -9,7 +9,7 @@ jobs:
         uses: actions/checkout@v2
 
       - name: Use Node 12
-        uses: actions/setup-node@v1
+        uses: actions/setup-node@v2
         with:
           node-version: 12.x