[BUGFIX] Calculate workspace module route correctly

Resolves: #82434
Related: #82406
Releases: master
Change-Id: I67182a131c2499713410807099f5d658a3858d63
Reviewed-on: https://review.typo3.org/54097


Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>