[TASK] Use SiteFinder directly in SlugHelper

Handling Sites via SiteMatcher is not necessary anymore,
as the SiteFinder does all the logic already, except for flushing
the rootline caches. The main reason (moving pages within DataHandler)
can be managed by adding this functionality into SlugHelper directly.

Resolves: #89225
Releases: master
Change-Id: I0e3fe151ebb99a154900f3335bef4a1db92ca4bf
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/61778


Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Frank Nägler <frank.naegler@typo3.org>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Frank Nägler <frank.naegler@typo3.org>