Be able to declare a provider explicitly requiring a specific role

[leezen]

So in this case it might be worth documenting how the effects the underlining providers as well. I don't think it's an uncommon thing to want to target another role in another account via a provider in code. But I'd expect by declaring a provider saying "you must be this role" and magically bypassing seems pretty dangerous. Bearing in mind the underlying profile could be a completely different set of credentials. I'd either want a hard failure telling me this can have unexpected outcomes, or for it to always use the role I declare(whether it be by profile name or roleArn)

The reasoning is when you shift a set of code from say your laptop (configured with AWS creds) to CI (likely env vars set) the behaviour can have considerably different outcomes.

Originally posted by @zoltrain in #952 (comment)

[stack72]

We have removed the code that stores the PROFILE in the stack as that was found to have bad consequences for teams using a profile that related to different credentials :)