[BUGFIX] Show images in preview of page module

For custom content elements with image these are shown
as thumbs in the list module but not in the page module.

This patch also renders the images when present just
like the bodytext.

Resolves: #59375
Releases: 6.2
Change-Id: If39e8b22af6144e5d6990a741559bd7574ee5e09
Reviewed-on: https://review.typo3.org/30598
Reviewed-by: Markus Klein
Tested-by: Markus Klein
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters