Add GitHub Actions configuration.

.github/workflows/test.yml

@@ -0,0 +1,36 @@
+name: Node.js CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  test:
+    runs-on: ubuntu-20.04
+    strategy:
+      matrix:
+        node-version: [[6.14, 10.x], [14.x], [16.x]]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      # Some modules used require a greater Node.js version than the lowest supported (listed above). Switch to the
+      # second Node.js version in the tuple before installing to game the system (and switch back later before running
+      # the actual tests).
+      - name: Use Node.js ${{ matrix.node-version[1] || matrix.node-version[0] }}
+        uses: actions/setup-node@v2
+        with:
+          node-version: ${{ matrix.node-version[1] || matrix.node-version[0] }}
+      - name: Install dependencies
+        run: yarn --frozen-lockfile
+      - name: Use Node.js ${{ matrix.node-version[0] }}
+        uses: actions/setup-node@v2
+        with:
+          node-version: ${{ matrix.node-version[0] }}
+      - name: Run test suite
+        run: yarn test
+        env:
+          # Set the API key for the integration tests. In the future, all tests will rely on snapshots. An API key will
+          # then only be required to update those snapshots. The API key can then be removed from this file.
+          API_KEY: test_4kQQbBMEFh8QAuKVaWdpKuRpVSsdVG