Revise chat interface description and contact info

Updated contact information for testing the chat interface.

Author: inodb

docs/ai-integrations/chat-interface.md

@@ -1,8 +1,6 @@
 # Chat Interface
 
-We've developed an AI-powered chat interface that allows users to ask questions about cBioPortal data in plain English. The chat interface is available at:
-
-**[https://chat.cbioportal.org/](https://chat.cbioportal.org/)**
+We've developed an AI-powered chat interface that allows users to ask questions about cBioPortal data in plain English. Please reach out if you'd like to test it on [email protected].
 
 > **Note:** This is a prototype and work in progress. Features and functionality are actively being developed and improved.