add linting to CI workflow

Author: angelo-v

.github/workflows/ci.yml

@@ -16,15 +16,16 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [10.x, 12.x, 14.x, 15.x]
+        node-version: [ 10.x, 12.x, 14.x, 15.x ]
         # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
 
     steps:
-    - uses: actions/checkout@v2
-    - name: Use Node.js ${{ matrix.node-version }}
-      uses: actions/setup-node@v1
-      with:
-        node-version: ${{ matrix.node-version }}
-    - run: npm ci
-    - run: npm run build --if-present
-    - run: npm test
+      - uses: actions/checkout@v2
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node-version }}
+      - run: npm ci
+      - run: npm run lint
+      - run: npm test
+      - run: npm run build --if-present