[TASK] Move database queries of linkvalidator to separate class

Move the database queries of EXT:linkvalidator into a new class
PagesRepository to make the functionality more flexible and easier to
test.

Resolves: #93006
Releases: master
Change-Id: Id068d0ef876005db11aceffb11ad968a08f377cf
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/67040


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Benni Mack <benni@typo3.org>