[8.6] Update supported k8s version for EKS (backport #4915)

[mergify]

We encountered an SDH ticket where a customer upgraded their EKS cluster to v1.25 and lost all their Pod Security Policy (PSP) findings because PSPs were removed in this version.
I don't believe we can claim to support all available EKS versions because our benchmark is not being updated, and we are likely to miss relevant findings.
It seems logical to tie our EKS support to the Kubernetes version we officially support. What do you think, @tinnytintin10?

Preview: KSPM FAQ

---

This is an automatic backport of pull request #4915 done by Mergify.

[mergify]

Cherry-pick of 55e1037 has failed:

On branch mergify/bp/8.6/pr-4915
Your branch is up to date with 'origin/8.6'.

You are currently cherry-picking commit 55e1037e.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   docs/cloud-native-security/cspm-faq.asciidoc
	both modified:   docs/cloud-native-security/kspm-faq.asciidoc

no changes added to commit (use "git add" and/or "git commit -a")

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[github-actions]

A documentation preview will be available soon.

• 🔨 Buildkite builds
• 📚 HTML diff
• 📙 Preview page

Request a new doc build by commenting

• Rebuild this PR: run docs-build
• Rebuild this PR and all Elastic docs: run docs-build rebuild

_{run docs-build is much faster than run docs-build rebuild. A rebuild should only be needed in rare situations.}

_{If your PR continues to fail for an unknown reason, the doc build pipeline may be broken. Elastic employees can check the pipeline status here.}

[benironside]

not applicable here