[BUGFIX] Fix overlapping FormEngine fields

Because of normal selectSingle fields having the css property
"width: auto", very long text forces those fields to span
the whole width of the text.

To fix this problem, the entire table layout has to fall.
FormEngine fields have now a solid grid layout. This
allows us more control over the layout. With this in place
the fix is pretty straight forward: "overflow: hidden"
for the wrapping div of the select field.

In addition, some cleanup has been done in GroupElement:
Empty aside divs are no longer rendered.

Resolves: #94688
Releases: master
Change-Id: I01a14dd2b2294d3260a90c1efecc402f742fabfb
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/71798


Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Oliver Bartsch <bo@cedev.de>