Add GitHub actions to test

Author: gemmadlou

.github/workflows/test.yml

@@ -0,0 +1,32 @@
+name: Tests
+on:
+  push:
+    branches:
+      - main
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node: [18, 20]
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+      - name: Setup Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: ${{ matrix.node }}
+      - name: Cache npm dependencies
+        uses: actions/cache@v3
+        id: npm-cache
+        with:
+          path: ~/.npm
+          key: ${{ runner.os }}-node-${{ matrix.node }}-npm-${{ hashFiles('**/package-lock.json') }}
+          restore-keys: |
+            ${{ runner.os }}-node-${{ matrix.node }}-npm-
+      - name: Install npm dependencies
+        run: npm ci
+      - name: Run Vitest tests
+        run: npm run test
+        env:
+          CI: true