Update documentation to indicate no IAM user role needed to run the app

[ericksod]

Context: As per a discussion group question, we noticed it was unclear that iAm permissions were not required to start up the app. Discussion group thread "So actually to run the app, you do not need to create a new IAM User so we should actually update that documentation."

A/C's:

• [ ] Update wording that may be misleading around when it is necessary to create a new IAM User here) "You will need an IAM user that can create access-keys and modify your billing settings." should not be there.