[BUGFIX] Respect docheader offset for anchors in page module

Resolves: #97036
Releases: main, 11.5
Change-Id: I4342011309a35233d278aec73e36a6dcf542babc
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/75131


Tested-by: core-ci <typo3@b13.com>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>