[FOLLOWUP][DOCS] 8.4 Documentation Part 1/2

Fix rendering of rst file which is part of the 8.4 changelog

Releases: master
Change-Id: I8aa75cdca1ad581eace9c0ada852a536044bc4af
Reviewed-on: https://review.typo3.org/50268


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Mathias Schreiber <mathias.schreiber@wmdb.de>
Tested-by: Mathias Schreiber <mathias.schreiber@wmdb.de>