Include minimal CI action

Author: eemeli

.github/workflows/ci.yaml

@@ -0,0 +1,15 @@
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+      - run: npm install
+      - run: npm test