test: Do "npm test" on GitHub Actions

.github/workflows/nodejs.yml

@@ -0,0 +1,21 @@
+name: CI (node.js)
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    env:
+      node-version: 10.7
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Use Node.js ${{ env.node-version }}
+      uses: actions/setup-node@v1
+      with:
+        node-version: ${{ env.node-version }}
+    - run: npm install
+    - name: Run headless test
+      uses: GabrielBB/xvfb-action@v1
+      with:
+        run: npm test

.travis.yml

@@ -1,11 +0,0 @@
-os: linux
-dist: xenial
-language: node_js
-node_js: '10.7'
-services: xvfb
-
-install:
-  - npm install
-
-script:
-  - npm test