[DOCS] Add master to changelog again

With the release of v10.4 the changes of master were removed
from the changelog. Now it is here again.

Resolves: #92730
Releases: master
Change-Id: I5a96dbfa3d62c426aba3b3033118bbe2f4379e52
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/66331


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Björn Jacob <bjoern.jacob@tritum.de>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Björn Jacob <bjoern.jacob@tritum.de>
Reviewed-by: Benni Mack <benni@typo3.org>