[BUGFIX] Make context menu trigger a `button`

The trigger to open the context menu is now
a proper `button` element.

Resolves: #103269
Releases: main, 12.4
Change-Id: Ia3932e4932ccd347b6816e08ee763420c70fbbba
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/83195


Reviewed-by: Andreas Kienast <a.fernandez@scripting-base.de>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Garvin Hicking <gh@faktor-e.de>
Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Andreas Kienast <a.fernandez@scripting-base.de>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Garvin Hicking <gh@faktor-e.de>