[8.x] Creates agentless troubleshooting page (backport #6184)

[mergify]

Fixes #6044 — creates a troubleshooting page for the new agentless integration.

Preview: Agentless integrations FAQESS, Serverless

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This is an automatic backport of pull request #6184 done by Mergify.

[mergify]

Cherry-pick of db188fa has failed:

On branch mergify/bp/8.x/pr-6184
Your branch is up to date with 'origin/8.x'.

You are currently cherry-picking commit db188fa3.
  (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:
	new file:   docs/getting-started/agentless-troubleshooting.asciidoc
	modified:   docs/getting-started/index.asciidoc
	new file:   docs/serverless/ingest/agentless-troubleshooting.asciidoc

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   docs/serverless/index.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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