fix: start the frontend in background

.github/workflows/playwright.yml

@@ -21,7 +21,7 @@ jobs:
     - name: Install Playwright Browsers
       run: npx playwright install --with-deps
     - name: start frontend server
-      run: npm start
+      run: npm start | cat - &
     - name: Run Playwright tests
       run: npx playwright test
     - uses: actions/upload-artifact@v3