[FEAT] Provide utilities to help users configure appropriate role claims

[artis3n]

Inside our organization, we have created internal utilities that assist developers with generating the appropriate configuration of bound_subject and additional_claims for their use cases. Those utilities are specific to workflows inside our organization, but we can still provide a more generic utility to assist organizations with figuring out what subject claim they should use and whether any additional claims should be added.

This could be a Go binary that asks some questions and generates out JSON files in the format we leverage in our example, or some other Terraform thing. I'd love to create HCL entities and have the ability to pass those into the module that unwrap into the appropriate bound_subject and additional_claims values. A la Go struct and a type expectation. But I don't believe the terraform go SDK helps much for a module author.

[artis3n]

One possible approach to assist is #99