docs: change config snippets to use defineConfig (#7546)

www/apps/resources/app/troubleshooting/_sections/other/cors-errors.mdx

@@ -4,18 +4,16 @@ You might see a log in your browser console, that looks like this:
 
 ![CORS error log](https://res.cloudinary.com/dza7lstvk/image/upload/v1668003322/Medusa%20Docs/Other/jnHK115_udgf2n.png)
 
-In your `medusa-config.js` , you should ensure that you've configured your CORS settings correctly. By default, the Medusa starter runs on port `9000`, Medusa Admin runs on port `7001`, and the storefront starters run on port `8000`.
-
-The default configuration uses the following CORS settings:
+In your `medusa-config.js` , you should ensure that you've configured your CORS settings correctly:
 
 ```js title="medusa-config.js"
-// CORS when consuming Medusa from admin
-const ADMIN_CORS = process.env.ADMIN_CORS || 
-  "http://localhost:7000,http://localhost:7001"
-
-// CORS to avoid issues when consuming Medusa from a client
-const STORE_CORS = 
-  process.env.STORE_CORS || "http://localhost:8000"
+module.exports = defineConfig({
+  projectConfig: {
+    http: {
+      storeCors: process.env.STORE_CORS,
+      adminCors: process.env.ADMIN_CORS,
+    }
+    // ...
+  }
+})
 ```
-
-If you wish to run your storefront or Medusa Admin on other ports, you should update the above settings accordingly.