[Fleet] Fix agent details page for agents without components

[jillguyonnet]

Summary

Fix a bug in the health reporting UI change in #158826 where the page breaks when the agent has no components.

Closes #159975

Checklist

• Unit or functional tests were updated or added to match the most common scenarios
• Any UI touched in this PR is usable by keyboard only (learn more about keyboard accessibility)
• Any UI touched in this PR does not create any new axe failures (run axe in browser: FF, Chrome)
• This renders correctly on smaller devices using a responsive layout. (You can test this in your browser)
• This was checked for cross-browser compatibility

[apmmachine]

🤖 GitHub comments

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Just comment with:

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[juliaElastic]

Thanks for fixing, and adding unit tests! 🚀

[jillguyonnet]

@elasticmachine merge upstream

[jillguyonnet]

@elasticmachine merge upstream

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: f2589d3

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
fleet	973.3KB	973.3KB	-22.0B

Unknown metric groups

ESLint disabled line counts

id	before	after	diff
enterpriseSearch	13	15	+2
securitySolution	416	420	+4
total			+6

Total ESLint disabled count

id	before	after	diff
enterpriseSearch	14	16	+2
securitySolution	497	501	+4
total			+6

History

• 💔 Build #136951 failed 493f1fb
• 💔 Build #136937 failed 82bbd26

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

cc @jillguyonnet

[elasticmachine]

Pinging @elastic/fleet (Team:Fleet)

[kibanamachine]

💔 All backports failed

Status	Branch	Result
❌	8.8	Backport failed because of merge conflicts

Manual backport

To create the backport manually run:

node scripts/backport --pr 160134

Questions ?

Please refer to the Backport tool documentation

[kibanamachine]

Friendly reminder: Looks like this PR hasn’t been backported yet.
To create automatically backports add the label auto-backport or prevent reminders by adding the backport:skip label.
You can also create backports manually by running node scripts/backport --pr 160134 locally

[kibanamachine]

Friendly reminder: Looks like this PR hasn’t been backported yet.
To create automatically backports add the label auto-backport or prevent reminders by adding the backport:skip label.
You can also create backports manually by running node scripts/backport --pr 160134 locally