fix(settings): federation scope menu a11y

[ShGKme]

• Resolves: [BITV] 9.4.1.2/6.3 - "Change scope" menus - Alle menus have been implemented using the aria-haspopup="menu" attribute, which informs users that a menu is being opened.(1) #41903

Summary

Use new radio behavior feature from NcActionButton.

• Remove intermediate FederationControlAction
  • NcActions doesn't fully support intermediate components
  • Fixes the menu role
  • Fixes keyboard navigation - Tab switches to the next UI element
• Use new type="radio"
  • Adjusts to menuitemradio role
• Remove custom styles to use new defaults
• Slightly fix padding on a small additional button

  Before	After

Screenshots

Before	After

We also have now the default design for radio menus. See discussion in nextcloud-libraries/nextcloud-vue#4744 (comment)

So I also removed the custom design. cc @nextcloud/designers

Old custom design	New default design

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

[JuliaKirschenheuter]

🥳

[jancborchardt]

Very nice, looks great to me design-wise. :)

[JuliaKirschenheuter]

/backport to stable28