feat(MenuBar): Make the menu bar role=toolbar and add focus handling

[susnux]

📝 Summary

• Resolves: [BITV] 9.2.4.3/3.9 - Toolbar focus handling #3863
• Part of [BITV] 9.4.1.2/3.16 - Custom editing menubar should be implemented using role=toolbar and not role=menubar. (2) #3911

For accessibility the toolbar should be implemented using role=toolbar. This requires custom focus handling[1] this is done by making only one element tabable / only one tab stop.

I had to remove the ActionEntry component as this functional component did not forward the template ref, so replaced it with a conditional component.

[1] https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/Roles/toolbar_role#description

🖼️ Screenshots

vokoscreenNG-2023-10-18_00-31-22.mp4

As you can see there is only one tab stop in the toolbar (the last used formatting option).

🚧 TODO

• Not part of that issue but we need to keep the focus on the menu item rather than jumping to the content after click.

🏁 Checklist

• Code is properly formatted (npm run lint / npm run stylelint / composer run cs:check)
• Sign-off message is added to all commits
• Tests (unit, integration and/or end-to-end) passing and the changes are covered with tests
• Documentation (README or documentation) has been updated or is not required

[Pytal]

Tested and works!

[juliushaertl]

Failures are unrelated, especially broken rich workspace seems to come from a recent server merge

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