[chore] Run Jest-based Unit Tests on PR via GHA

.github/workflows/test.yml

@@ -0,0 +1,21 @@
+name: Run Unit Tests
+
+on: [pull_request]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Set up Node.js
+      uses: actions/setup-node@v3
+      with:
+        node-version: 18
+
+    - name: Install dependencies
+      run: npm install
+
+    - name: Run Unit Tests
+      run: npm run test