[TASK] Clean up page layout grid classes

Code cleanup of internal page layout grid classes.

Resolves: #102801
Releases: main
Change-Id: I3294d0d3db64ad9df91ce42f40e0a8e7535013dc
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/82413


Tested-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: Oliver Klee <typo3-coding@oliverklee.de>
Reviewed-by: Benni Mack <benni@typo3.org>