Make Basic Chatbot Server Publicly Accessible

In [configuration docs](https://github.com/mongodb/chatbot/blob/main/docs/docs/server/configure.md) there's a reference to [Basic Chatbot Server](https://github.com/mongodb/chatbot/blob/main/examples/basic-chatbot-server/src/index.ts) that seems should be public, but I'm getting 404'd. From the configuration docs this seems like something intended to be public. 