ci: use Github Actions (#9)

Author: goto-bus-stop

.github/workflows/ci.yml

@@ -0,0 +1,22 @@
+name: CI
+
+on: [push, pull_request]
+
+jobs:
+  test:
+    name: Tests
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node-version: [10.x, 12.x, 14.x, 15.x]
+    steps:
+      - name: Checkout sources
+        uses: actions/checkout@v2
+      - name: Install Node.js ${{matrix.node-version}}
+        uses: actions/setup-node@v2
+        with:
+          node-version: ${{matrix.node-version}}
+      - name: Install dependencies
+        run: npm install
+      - name: Run tests
+        run: npm test