chore(ci): use LTS version

.github/workflows/build.yml

@@ -11,16 +11,12 @@ jobs:
   build:
     runs-on: ubuntu-latest
 
-    strategy:
-      matrix:
-        node-version: [lts/fermium]
-
     steps:
       - uses: actions/checkout@v2
-      - name: Use Node.js ${{ matrix.node-version }}
+      - name: Set up Node.js
         uses: actions/setup-node@v1
         with:
-          node-version: ${{ matrix.node-version }}
+          node-version: lts/fermium
       - name: Install Dependencies
         run: npm ci
       - name: Check Code Style