docs: add EKS Pod Identity steps for Kyverno

[abdollahShahid]

Closes #1289

This PR adds EKS Pod Identity instructions to the existing Kyverno AWS IRSA blog post.

This update documents how to:

• Use EKS Pod Identity as an alternative to IRSA for Kyverno on Amazon EKS.
• Create the IAM trust policy for pods.eks.amazonaws.com.
• Create and attach an IAM role for the Kyverno admission controller.
• Create the EKS Pod Identity association for the kyverno-admission-controller ServiceAccount.
• Restart the admission controller so credential environment variables are injected.
• Verify the association and Pod Identity credential environment variables.

The existing IRSA instructions are kept intact for users who still use IRSA.

Testing

• Ran npx prettier --check src/content/blog/aws-irsa/index.md
• Ran npm run build

[welcome]

Thanks for opening your first Pull Request here! Please check out our Contributing guidelines and confirm that you Signed off.

[Copilot]

Pull request overview

This PR updates the existing “Kyverno + AWS IRSA” blog post to also document Amazon EKS Pod Identity as an alternative way to grant Kyverno’s admission controller AWS permissions for image verification workflows.

Changes:

• Added a new “Enabling EKS Pod Identity” section with IAM trust policy, role creation/attachment, Pod Identity association, restart, and verification steps.
• Kept the existing IRSA instructions intact and updated the conclusion to reference both Pod Identity and IRSA.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Suhani95]

@abdollahShahid Nice docs update overall.
Could we also document the minimum supported EKS and AWS CLI versions required for Pod Identity? Since create-pod-identity-association is relatively new, adding prerequisites would help reduce setup confusion.