Provides backwards compatibility for Kubernetes 1.34 control plane metrics

[musa-asad]

Description of the issue

K8s 1.34 introduced breaking changes to control plane metrics by splitting labels into group and resource components and renaming apiserver_storage_objects to apiserver_resource_objects. This breaks existing CloudWatch dashboards and alerts.

Description of changes

• Implements applyK8s134Compatibility function in Prometheus input plugin
• Renames apiserver_resource_objects metric to apiserver_storage_objects
• Combines resource and group labels into legacy label formats
• Transforms K8s 1.34+ control plane metrics back to pre-1.34 format for backward compatibility

License

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Tests

Unit tests.

Requirements

Before commiting your code, please do the following steps.

1. Run make fmt and make fmt-sh
2. Run make lint

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Integration Tests

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[github-actions]

This PR was marked stale due to lack of activity.