Create ci.yml

Set up CI/CD using GitHub actions.

.github/workflows/ci.yml

@@ -0,0 +1,31 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v2
+
+    - name: Set up Node.js
+      uses: actions/setup-node@v2
+      with:
+        node-version: '18'
+
+    - name: Install dependencies
+      run: npm install
+
+    - name: Build the project
+      run: npm run build
+
+    - name: Run tests
+      run: npm test