consider deprecating CLI's IAM Policy page in favor of managed policy

[josefaidt]

ref: https://github.com/aws-amplify/docs/issues/3422 page: https://docs.amplify.aws/cli/reference/iam/ policy: AdministratorAccess-Amplify

[josefaidt]

We should keep this doc and be more clear about the intent where this is a reference to provide least amount of privilege to the IAM user, where AdministratorAccess-Amplify is sufficient for most cases

[ykethan]

closing the issue as this page has been deprecated.