Revert "[BUGFIX] Display human-readable preview of FlexForm values"

This patch reverts #91148 and #97897.

This change had some side effects in FlexForm value
displaying outside the intended diff-view.

Resolves: #97904
Related: #91148
Related: #97897
Releases: main, 11.5
Change-Id: I6d5af76dea80b457de5a690e3065ccb700b2a507
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/75113


Tested-by: core-ci <typo3@b13.com>
Tested-by: Nikita Hovratov <nikita.h@live.de>
Reviewed-by: Nikita Hovratov <nikita.h@live.de>