add overflow:visible to allow the workspace action menu to be highlighted

[manutdkid77]

Description

On Mozilla Firefox, the uui-popover-container element would inherit a style of overflow:clip, this would hide the highlight of the Save/Publish menu on Firefox.

Setting overflow:visible to uui-popover-container allows the highlight of this element to be visible when tabbed into on Firefox browsers.

This fixes #16208

[github-actions]

Hi there @manutdkid77, thank you for this contribution! 👍

While we wait for one of the Core Collaborators team to have a look at your work, we wanted to let you know about that we have a checklist for some of the things we will consider during review:

• It's clear what problem this is solving, there's a connected issue or a description of what the changes do and how to test them
• The automated tests all pass (see "Checks" tab on this PR)
• The level of security for this contribution is the same or improved
• The level of performance for this contribution is the same or improved
• Avoids creating breaking changes; note that behavioral changes might also be perceived as breaking
• If this is a new feature, Umbraco HQ provided guidance on the implementation beforehand
• 💡 The contribution looks original and the contributor is presumably allowed to share it

Don't worry if you got something wrong. We like to think of a pull request as the start of a conversation, we're happy to provide guidance on improving your contribution.

If you realize that you might want to make some changes then you can do that by adding new commits to the branch you created for this work and pushing new commits. They should then automatically show up as updates to this pull request.

Thanks, from your friendly Umbraco GitHub bot 🤖 🙂

[emmagarland]

Hi @manutdkid77 !

Thanks for your PR to fix #16208, where the save/publish workspace action menu is not highlighted in Firefox.

One of the Core Collaborators team will review this as soon as possible.

Best wishes

Emma