PR#6911 Backport for 1.30: Fix/aws asg unsafe decommission #5829

[kmsarabu]

PR#6911 Backport for 1.30: Fix/aws asg unsafe decommission #5829

This merge resolves an issue in the Kubernetes Cluster Autoscaler where actual instances within AWS Auto Scaling Groups (ASGs) were incorrectly decommissioned instead of placeholders. The updates ensure that placeholders are exclusively targeted for scaling down under conditions where recent scaling activities have failed. This prevents the accidental termination of active nodes and enhances the reliability of the autoscaler in AWS environments.

What type of PR is this?
/kind bug

What this PR does / why we need it:
This PR prevents the Kubernetes Cluster Autoscaler from erroneously decommissioning actual nodes during scale-down operations in AWS environments, which could lead to unintended service disruptions.

Which issue(s) this PR fixes:
Fixes #5829

Special notes for your reviewer:
Does this PR introduce a user-facing change?
Fix an issue in the Kubernetes Cluster Autoscaler where actual AWS instances could be incorrectly scaled down instead of placeholders.

[k8s-ci-robot]

Hi @kmsarabu. Thanks for your PR.

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[Shubham82]

/ok-to-test

[Shubham82]

Thanks @kmsarabu
/lgtm

[gjtempleton]

Thanks!

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: gjtempleton, kmsarabu

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• cluster-autoscaler/cloudprovider/aws/OWNERS [gjtempleton]

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