add: allowed-account-ids (to prevent accidents)

[ghostsquad]

Similar to the terraform provider feature:

allowed_account_ids - (Optional) List of allowed AWS account IDs to prevent you from mistakenly using an incorrect one (and potentially end up destroying a live environment). Conflicts with forbidden_account_ids.

[peterwoodworth]

I can see how this would be useful, thank you for the suggestion! We should be able to make a check for this pretty easily