[TASK] Migrate ReferenceIndex to Doctrine

Resolves: #77389
Releases: master
Change-Id: I291cb8a218e19f38e64d879a8bd80d5a29a6a1f7
Reviewed-on: https://review.typo3.org/49358


Reviewed-by: Mathias Schreiber <mathias.schreiber@wmdb.de>
Tested-by: Mathias Schreiber <mathias.schreiber@wmdb.de>
Tested-by: Bamboo TYPO3com <info@typo3.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>