AWS::CloudFormation::Stack - RoleARN

## 2. Scope of request
[CreateStack](https://docs.aws.amazon.com/AWSCloudFormation/latest/APIReference/API_CreateStack.html) supports `RoleARN` attribute. But [`AWS::CloudFormation::Stack`](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-stack.html) doesn't support it.

## 3. Expected behavior

It creates a nested stack with given `RoleARN`.

## 6. Category (required) - Will help with tagging and be easier to find by other users to +1
Management (CloudFormation)

## 7. Any additional context (optional)
This could be an another possible workaround for https://github.com/aws/containers-roadmap/issues/554 ?
Workarounds are reinvented several times separately by different teams in AWS (AWS QuickStart team uses [custom type](https://github.com/aws-quickstart/quickstart-amazon-eks/)), AWS CDK team uses [CustomResource](https://github.com/aws/aws-cdk/blob/master/packages/%40aws-cdk/aws-eks/README.md))
It is the best that EKS's CreateCluster API is fixed. But if it is not possible, then I think workaround with a nested stack with RoleARN would be more simpler and stable.

Start with the linked CreateStack API and AWS::CloudFormation::Stack documentation to compare the supported attributes. Confirm the nested-stack RoleARN behavior and any service-side requirements; done means the resource accepts RoleARN and creates the nested stack with that role, with the documentation updated accordingly.

Written by the indexing model from the issue text.