Update workflow definition

.github/workflows/ci.yml

@@ -0,0 +1,23 @@
+name: CI
+
+on: [push, pull_request]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+    - name: Setup node
+      uses: actions/setup-node@v1
+      with:
+        node-version: '12.x'
+    - name: Install dependencies
+      run: npm ci
+    - name: Build
+      run: npm run build --if-present
+    - name: Run tests
+      run: npm test
+      env:
+        CI: true

.github/workflows/nodejs.yml

@@ -1,24 +0,0 @@
-name: Node.js CI
-
-on: [push]
-
-jobs:
-  build:
-
-    runs-on: ubuntu-latest
-
-    strategy:
-      matrix:
-        node-version: [10.x, 12.x]
-
-    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
-      env:
-        CI: true