[TASK] Fix absolute documentation links in the Core

The outdated links in EXT:install are improved in
https://forge.typo3.org/issues/97885

Releases: main, 11.5
Resolves: #97886
Change-Id: I25979df8f9f322461ffc6d03ab9030240c2e0e8a
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/75067


Tested-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Nikita Hovratov <nikita.h@live.de>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Nikita Hovratov <nikita.h@live.de>