Update actions/setup-node action to v2

Author: renovate-bot

.github/workflows/build.yml

@@ -21,7 +21,7 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: Use Node.js ${{ matrix.node-version }}
-      uses: actions/setup-node@v1
+      uses: actions/setup-node@v2
       with:
         node-version: ${{ matrix.node-version }}
     - run: yarn