[EuiButtonGroup] Add title when in iconOnly mode

[lejara]

Summary

Fixes (#5180)

Checklist

• [ ] Check against all themes for compatibility in both light and dark modes
• [ ] Checked in mobile
• Checked in Chrome, Safari, Edge, and Firefox
• [ ] Props have proper autodocs and playground toggles
• [ ] Added documentation
• [ ] Checked Code Sandbox works for any docs examples
• [] Added or updated jest tests
• [ ] Checked for breaking changes and labeled appropriately
• [ ] Checked for accessibility including keyboard-only and screenreader modes
• A changelog entry exists and is marked appropriately

[kibanamachine]

Since this is a community submitted pull request, a Jenkins build has not been kicked off automatically. Can an Elastic organization member please verify the contents of this patch and then kick off a build manually?

[cla-checker-service]

💚 CLA has been signed

[cchaos]

🎉 Thanks for the PR @lejara !!

Would you please sign the CLA linked below if you have not done so already. Be sure to use the same email address linked to your Github account.

[cchaos]

Thanks for the update. I'll get our CI (Jenkins) started for you which will run our tests and get a preview built.

Jenkins, test this

[kibanamachine]

Preview documentation changes for this PR: https://eui.elastic.co/pr_5199/

[cchaos]

Flakey test.

Jenkins, test this

[kibanamachine]

Preview documentation changes for this PR: https://eui.elastic.co/pr_5199/

[cchaos]

🙌 Simple fixes are my favorite!

I double-checked this locally too by also testing that consumers can override the auto-generated title still and they can.

It looks like the snapshots won't update because it can' do the innerText calculation so this title prop will never show up in the snapshots.

[thompsongl]

jenkins test this

[kibanamachine]

Preview documentation changes for this PR: https://eui.elastic.co/pr_5199/