[BUGFIX] Remove extra card stylings introduced with Bootstrap 5

Remove background of card header and bottom/top border of
card header/footer so the style does not change from TYPO3 v10
to v11.

Also re-add checkbox-type-toggle absolute positioning of the
hidden checkbox in order to avoid upper spacing above checkbox
toggle elements (causes too much spacing in feature cards).

Resolves: #93120
Releases: master
Change-Id: Ibd2e87c4e4284218390c4e8d0722fcdee87de92f
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/67231


Tested-by: Benjamin Franzke <bfr@qbus.de>
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Benjamin Franzke <bfr@qbus.de>
Reviewed-by: Benni Mack <benni@typo3.org>