feat: add test workflow

.github/workflows/test.yml

@@ -0,0 +1,16 @@
+name: Test JSONata
+on:
+    push:
+        branches: [stedi-main]
+    pull_request:
+        branches: [stedi-main]
+jobs:
+    test:
+        runs-on: ubuntu-latest
+        steps:
+            - uses: actions/checkout@v3
+            - uses: actions/setup-node@v3
+              with:
+                  node-version: 20
+            - run: npm install
+            - run: npm test