[BUGFIX] EXT:form - fix clicks on checkbox labels in IE/Edge

Add the "for" attribute to help Internet Explorer and Edge to target
the actual checkbox field, not the hidden field in front of it.

Resolves: #83417
Releases: master, 8.7
Change-Id: I603f95fc18df57f64d5dde8aefe6338c47b29536
Reviewed-on: https://review.typo3.org/55203


Reviewed-by: Mathias Schreiber <mathias.schreiber@typo3.com>
Tested-by: Mathias Schreiber <mathias.schreiber@typo3.com>
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>