feat: adding controlPlaneScalingConfig to Cluster

[notSoWiseOldMan]

Reason for this change

controlPlaneScalingConfig was an option added to EKS clusters recently. This was added to CFN and the level 1 structure. This PR adds it to the level 2 construct.

Description of changes

• Added controlPlaneScalingConfig to Cluster.
• Added section to the README
• Added unit tests for basic controlPlaneScalingConfig validation

Describe any new or updated permissions being added

None

Description of how you validated changes

Tested with unit tests. CFN side changes have been tested separately and this change is not doing anything more than just passing through the level 1 cfnCluster properties.

Checklist

• My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[aws-cdk-automation]

The pull request linter fails with the following errors:

❌ Features must contain a change to an integration test file and the resulting snapshot.

If you believe this pull request should receive an exemption, please comment and provide a justification. A comment requesting an exemption should contain the text Exemption Request. Additionally, if clarification is needed, add Clarification Request to a comment.

[github-actions]

	Tests	Passed ❌️	Skipped	Failed
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[github-actions]

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[notSoWiseOldMan]

I am able to get this build to succeed locally in devcontainer. Unfortunately, I am struggling with the integ tests to generate the new snapshot. It is unable to find the integ test files. I used the below command bc the command documented in the contributing guide yarn integ integ.eks-cluster.js fails with error Command "integ" not found.

➜  aws-cdk git:(eks/controlPlaneScalingConfig) npx integ-runner packages/@aws-cdk-testing/framework-integ/test/aws-eks/test/integ.eks-cluster.ts --update-on-failed
No such integ test: packages/@aws-cdk-testing/framework-integ/test/aws-eks/test/integ.eks-cluster.ts
Available tests: 

Verifying integration test snapshots...


Snapshot Results: 

Tests:    0 passed, 0 total

Running integration tests for failed tests...

Running in parallel across regions: us-east-1, us-east-2, us-west-2

Test Results: 

Tests:    0 passed, 0 total

Can a maintainer run the integ test and update the snapshot for me?