[TASK] Remove moduleMenuCollapsable from the reserved word list

Since this functionnality was removed frome the core, the word
is not reserved anymore.

Resolves: #76887
Releases: master
Change-Id: I67727c57de8bba1ff19903932dd11b3cd1316caa
Reviewed-on: https://review.typo3.org/48740


Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Bamboo TYPO3com <info@typo3.com>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>