[BUGFIX] Fix workspace select / deselect all buttons

The "select all" and "deselect all" buttons in the "Send to stage"
modal in workspaces are now proper button tags.

This also allowed to remove the superfluous preventDefault()
call in JavaScript.

Resolves: #92776
Releases: master, 10.4
Change-Id: I1480ad06df501a4064609e516c8b10d6b4567425
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/66453


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Michael Telgkamp <michael.telgkamp@mindscreen.de>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Michael Telgkamp <michael.telgkamp@mindscreen.de>
Reviewed-by: Benni Mack <benni@typo3.org>