Adding troubleshooting section for Elastic Agent on Kubernetes and Kustomize

[eedugon]

I've added a new section on the troubleshooting document for Kubernetes related Elastic Agents.

Closes https://github.com/elastic/kibana/issues/186382

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[eedugon]

@kilfoyle : I'm done with Brandon suggestions, only a tiny change is pending :)

Feel free to share your feedback and review.

In my opinion we should probably end up creating a complete document focused on Agent on Kubernetes troubleshooting, but even though this might be a good start.

Also note that the section I'm adding is a bit different in nature as the other sections of the troubleshooting document because I didn't have a list of exact issues to report, and it's a bit more generic about the manifest installation with kustomize and possible issues.

If you want to add specific issues I would be more than happy to add content if you share, or if you believe we should structure this in a different way.

[kilfoyle]

@eedugon I think this looks terrific! I added just a few super minor comments.

In my opinion we should probably end up creating a complete document focused on Agent on Kubernetes troubleshooting, but even though this might be a good start.

Yeah, I agree that we eventually should break this out as a separate page, especially if we expand it with more info. For this PR, though, I think what you're adding is perfect.

I'm not aware of any other related content to add right now, but it's nice to have a good place for it. :-)

[eedugon]

thanks a lot @kilfoyle for the comments and suggestions!!

[eedugon]

@gizas : latest commit 7d7f88f35eb7dfc7d92292c432d14d2a13a6f361 includes the changes about:

• added note for ksm and elastic agent namespace.
• added link for leadership election.
• minor improvements.

Feel free to take a look and share your thoughts before merging ;)