Fixed PlayWright config

no issue

Using multiple workers could cause Stripe to be removed from one test while another test was using it.

ghost/core/playwright.config.js

@@ -6,7 +6,8 @@ const config = {
     use: {
         // Use a single browser since we can't simultaneously test multiple browsers
         browserName: 'chromium',
-        baseURL: process.env.TEST_URL ?? 'http://localhost:2368'
+        baseURL: process.env.TEST_URL ?? 'http://localhost:2368',
+        headless: false
     }
 };