Creates agentless troubleshooting page

[benironside]

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

Preview: Agentless integrations FAQESS, Serverless

[github-actions]

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[mergify]

This pull request does not have a backport label. Could you fix it @benironside? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• v7.x is the label to automatically backport to the 7.x branch.
• v7./d./d is the label to automatically backport to the 7./d branch. /d is the digit

NOTE: backport-skip has been added to this pull request.

[mergify]

This pull request is now in conflicts. Could you fix it @benironside? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch upstream
git checkout -b 6044-agentless-faq-2 upstream/6044-agentless-faq-2
git merge upstream/main
git push upstream 6044-agentless-faq-2

[nastasha-solomon]

Lot's of great troubleshooting content here. I left some edits for your consideration. Hope they help!

[jmikell821]

Thanks for pulling this together! Double check all the fleet attribute references; I tried to get them all. And, of course, suggestions apply to both doc sets.