adds demo link for dashboard

Author: rishabhpoddar

v2/userdashboard/about.mdx

@@ -8,6 +8,15 @@ hide_title: true
 
 With the user management dashboard, you can view the list of users on SuperTokens and be able to easily view, modify or delete their sessions, metadata, roles and account info.
 
+## Live demo
+
+We have a read-only user management dashboard (with fake data), and it can be accessed [on this link](https://dashboard.demo.supertokens.com/auth/dashboard). The credentials for logging in are:
+
+```text
+email: [email protected]
+password: abcd1234
+```
+
 ## Complete quick setup
 
 Before you can use the user management dashboard make sure to complete setting up SuperTokens on your backend by following the quick setup guide for the recipe of your choice, view all recipes [here](/docs/guides)