Reflect new structure of cookie config object since RW 6.4

See #9248

docs/docs/auth/dbauth.md

@@ -316,14 +316,19 @@ These options determine how the cookie that tracks whether the client is authori
 
 ```javascript
 cookie: {
-  HttpOnly: true,
-  Path: '/',
-  SameSite: 'Strict',
-  Secure: true,
-  // Domain: 'example.com',
+  attributes: {
+    HttpOnly: true,
+    Path: '/',
+    SameSite: 'Strict',
+    Secure: true,
+    // Domain: 'example.com',
+  },
+  // name: 'session_%port%' 
 }
 ```
 
+As shown above the cookie name defaults to `'session_%port%'` but can also be customized, where `%port% will be replaced with the port the api server is running on.
+
 ### CORS config
 
 If you're using dbAuth and your api and web sides are deployed to different domains then you'll need to configure CORS for both GraphQL in general and dbAuth. You'll also need to enable a couple of options to be sure and send/accept credentials in XHR requests. For more info, see the complete [CORS doc](cors.md#cors-and-authentication).