[EKS] [IAM]: Add ability to set permissions boundary in IAM console when creating role for EKS Node Groups

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**Tell us about your request**

Add form option to select permissions boundary when creating role for EKS node groups.

**Which service(s) is this request for?**

EKS

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**

In a sandbox-type environment and for those learning, the AWS console is usually the first place to go to provision resources.

**Are you currently working around this issue?**

I cannot. Our SCP denies the ability to create roles without a permissions boundary and required policy cannot be attached to a customer role.

**Additional context**

**Attachments**
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No files, tests, or entry points are identified in the issue. Start by locating the EKS node-group role creation form and its permissions-boundary support; done means the console lets users select a boundary when creating the role.

Written by the indexing model from the issue text.