[8.x] [Jan 28] GA for third-party response actions (backport #6471)

[mergify]

Resolves #6397.

Previews

ESS:

• Third-party response actions
• Configure third-party response actions

Serverless:

• Third-party response actions
• Configure third-party response actions

---

This is an automatic backport of pull request #6471 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 285d9d3 has failed:

On branch mergify/bp/8.x/pr-6471
Your branch is up to date with 'origin/8.x'.

You are currently cherry-picking commit 285d9d30.
  (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)

Changes to be committed:
	modified:   docs/management/admin/response-actions-config.asciidoc
	modified:   docs/management/admin/third-party-actions.asciidoc

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   docs/serverless/endpoint-response-actions/response-actions-config.asciidoc
	deleted by us:   docs/serverless/endpoint-response-actions/third-party-actions.asciidoc

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]

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