Re-introduce AWSManagedCluster for EKS ClusterClass support

[sedefsavas]

This issue is to track re-implementation of AWSManagedCluster for ClusterClass support (for details of why we need to do this is here).

We need to decide the best option to implement for CAPA considering the options in managed K8s proposal.

As a follow up to this, AWSManagedControlPlaneTemplate and AWSManagedClusterTemplate resources are needed for ClusterClass support:
#3166

[k8s-ci-robot]

@sedefsavas: This issue is currently awaiting triage.

If CAPA/CAPI contributors determines this is a relevant issue, they will accept it by applying the triage/accepted label and provide further guidance.

The triage/accepted label can be added by org members by writing /triage accepted in a comment.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[k8s-ci-robot]

@richardcase: The provided milestone is not valid for this repository. Milestones in this repository: [Backlog, v1.4.2, v1.5.0, v1.6.0, v1.x, v2.x]

Use /milestone clear to clear the milestone.

In response to this:

/milestone v2.X

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[richardcase]

/milestone v2.x

[k8s-triage-robot]

The Kubernetes project currently lacks enough contributors to adequately respond to all issues and PRs.

This bot triages issues and PRs according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Mark this issue or PR as fresh with /remove-lifecycle stale
• Mark this issue or PR as rotten with /lifecycle rotten
• Close this issue or PR with /close
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle stale