Add GitHub workflow

.github/workflows/main.yml

@@ -0,0 +1,24 @@
+name: Main
+on: push
+
+jobs:
+  test-and-release:
+    name: Test and release
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v1
+        with:
+          node-version: 12
+
+      - name: Install
+        run: npm ci
+
+      - name: Lint
+        run: npm run lint
+
+      - name: Test
+        run: npm test

.lintstagedrc.json

@@ -1,4 +1,4 @@
 {
   "*.js": ["eslint --fix", "prettier --write"],
-  "*.{css,json,md}": "prettier --write"
+  "*.{css,json,md,yml": "prettier --write"
 }