[BUGFIX] ConstantEditor: Make boolean fields UI working in Edge/IE

Move the hidden form field out of the label tag to ensure clicking
the label's content (eg. fa icon) really toggles the checkbox.

Resolves: #82998
Releases: master, 8.7, 7.6
Change-Id: Id4293b4109c82a9e6410e113a5b5560ffd1b75d4
Reviewed-on: https://review.typo3.org/54682


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Jigal van Hemert <jigal.van.hemert@typo3.org>
Tested-by: Jigal van Hemert <jigal.van.hemert@typo3.org>
Reviewed-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>
Tested-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>