Enable option to allow anonymous users

[subha-aws]

Is your feature request related to a problem? Please describe.
I want my chatbot to be available publicly, Its a customer service rep.

Describe the feature you'd like
Allow option on deployment to enable anonymous users.

Additional context
Add any other context or screenshots about the feature request here.

[knihit]

@subha-aws thank you for the feedback. Some considerations to open up the use case publicly (without authentication).

1. An unauthenticated implementation (publicly open) may run into exponential cost for customers. (Refer: sample cost table.
2. Configure Identity federation. Amazon Cognito supports OpenID and most standard identity providers.

As a backlog item, we will add instructions in the implementation guide in a future release that provides more information on customizing authentication for the front-end and Api Gateway.