[BUGFIX] Deactivate link element's explanation toggle after change

Dynamically fetching/applying additional data for the link explanation
seems to be overdone, so we simply deactivate the toggle button and
remove the icon after selection/modification of the link target.
After persisting the record, the updated link explanation
will be visible.

Resolves: #88737
Releases: master, 9.5
Change-Id: I679abb2178aedfc8a29cccace99950a3a8acaab6
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/61422


Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Alexander Stehlik <alexander.stehlik@gmail.com>
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Susanne Moog <look@susi.dev>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Alexander Stehlik <alexander.stehlik@gmail.com>
Reviewed-by: Susanne Moog <look@susi.dev>