[EKS] [request]: tag Kubernetes managed nodes with node-role.kubernetes.io/<node-group-name>=true, reopen #733 issue

### Community Note

* Please vote on this issue by adding a 👍 [reaction](https://blog.github.com/2016-03-10-add-reactions-to-pull-requests-issues-and-comments/) to the original issue to help the community and maintainers prioritize this request
* Please do not leave "+1" or "me too" comments, they generate extra noise for issue followers and do not help prioritize the request
* If you are interested in working on this issue or have submitted a pull request, please leave a comment

**Tell us about your request**
I suggest this issue #733 reopen. Because I think this issue is not resolved.
After creating the node group, running the 'kubectl get node' command gives the following result:
```
NAME STATUS ROLES AGE VERSION
ip-10-0-158-206.ap-northeast-2.compute.internal Ready 8m37s v1.15.10-eks-bac369
```

If this issue is resolved, additional configuration is not required to assign the node role and you can see the following result.
```
NAME STATUS ROLES AGE VERSION
ip-10-0-17-82.ap-northeast-2.compute.internal Ready worker 27d v1.15.10-eks-bac369
```

**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?**
You can see the #733 issue.

**Are you currently working around this issue?**
You can see the #733 issue.

Start by reviewing the referenced issue #733 and the EKS node output in this request. Confirm the intended node-role.kubernetes.io/=true behavior for managed nodes; done means kubectl get node reports the expected worker role without additional configuration.

Written by the indexing model from the issue text.