Revise EKS node pool surge node logic now that NASGMinInstancesInService is available in CF templates

[pregnor]

Is your feature request related to a problem? Please describe.

The EKS node pool update surge node handling logic was implemented using NASGMaxSize and NASGMaxBatchSize values only.

Describe the solution you'd like to see

We should double check the custom logic whether the newly available NASGMinInstancesInService attribute can help us replacing parts or the whole of the EKS node pool update surge node implementation logic using the built-in features of the CloudFormation template and its backing services.

Describe alternatives you've considered

If the supported max batch size and min instances in services cannot replace the custom surge logic, we can keep the current logic intact.

Additional context

AWS CloudFormation template UpdatePolicy attribute