Stabilize the ConfirmDialoc component

[afercia]

Description

See #59825 (comment)

The ConfirmDialog component was merged more than 2 years ago in #34153 but it is still marked as 'experimental'. Worth considering to stabilize it.

To recap why it was introduced, see the related issues #16583 and #33937

• The native window.confirm() isn't an ideal experience as we're unable to customise the OK button to have a more descriptive label.
• Major browsers - starting with Chrome - will soon restrict the alert/confirm/prompt functions from being used from within cross-origin iframes.

The ConfirmDialog component seems to work well tor the editor needs. From an accessibility perspective, I think it only needs a lable for the dialot (the element with role=dialog) as it's currently unlabeled.

Step-by-step reproduction instructions

N/A
To see an example of a ConfirmDialog in action:

• Go to the site editor, view mode.
• In the navigation panel, click Design > Navigation > {menu name} > Actions ellipsis button > Delete
• Observe the confirmation dialog.

Screenshots, screen recording, code snippet

No response

Environment info

No response

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes