[9.0](backport #7241) [helm]: bump elastic-agent helm chart ksm dependency

[mergify]

What does this PR do?

This PR bumps the kube-state-metrics (KSM) subchart dependency in the Elastic Agent Helm chart to its latest version.

Specifically, it updates kube-state-metrics from version 5.28.0 to 5.30.1, along with the corresponding digest update in Chart.lock. The generated manifests and configuration files have been updated to reflect this change, including updating the associated KSM application version from 2.14.0 to 2.15.0.

Why is it important?

Keeping dependencies up to date ensures compatibility with the latest features, security patches, and performance improvements. This update helps maintain alignment with the latest kube-state-metrics Helm chart from the Prometheus community.

Checklist

• I have read and understood the pull request guidelines of this project.
• My code follows the style guidelines of this project.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• I have made corresponding changes to the default configuration files.
• I have added tests that prove my fix is effective or that my feature works.
• I have added an entry in ./changelog/fragments using the changelog tool.
• I have added an integration test or an E2E test.

Disruptive User Impact

This change should not introduce any disruptive impact.

How to test this PR locally

Install any of the kubernetes examples with ksm enabled in a k8s cluster

Related issues

N/A

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This is an automatic backport of pull request #7241 done by Mergify.

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[elastic-sonarqube]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarQube

[elasticmachine]

💚 Build Succeeded

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• Commit: 334c3c4

cc @pkoutsovasilis