[DOCS] Introduce unique link targets per Changelog

Changelog entries can be linked even if the
file is renamed or moved.

In the future this enables us to get rid of different
link syntax and
only use the most well known :ref:`deprecation-12345`
syntax.

Resolves: #96329
Releases: main
Change-Id: I3c1c6c48e3a2d381974752f1c837a04e59036ffd
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/76667


Tested-by: core-ci <typo3@b13.com>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Lina Wolf <112@linawolf.de>
Reviewed-by: Lina Wolf <112@linawolf.de>