Added test runner workflow.

.github/workflows/tests.yml

@@ -0,0 +1,27 @@
+name: Run tests
+
+on: [push, pull_request]
+
+jobs:
+  test:
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macOS-latest] # windows-latest
+        version: [16, 18, 20]
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+    - name: "Checkout code"
+      uses: actions/checkout@v4
+
+    - name: Set up node
+      uses: actions/setup-node@v4
+      with:
+        node-version: ${{ matrix.version }}
+
+    - name: Install Node deps
+      run: npm i
+
+    - name: Run the tests
+      run: npm run test