Add GitHub action to lint, build and test

Author: nigelmegitt

.github/workflows/build.yml

@@ -0,0 +1,29 @@
+name: Build 🛠️
+
+on:
+  workflow_dispatch: # can call manually
+  push:
+    branches:
+      - master
+  pull-request:
+
+jobs:
+  test:
+    name: Run the tests
+    strategy:
+      matrix:
+         node-version: ['18.x', '20.x']
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Use Node.js ${{ matrix.node-version }}
+      uses: actions/setup-node@v4
+      with:
+        node-version: ${{ matrix.node-version }}
+        cache: 'npm'
+    - run: npm ci
+    - run: npm run lint
+    - run: npm run build
+    - run: npm run test