[TASK] Add tests for BackendUtility::splitTable_Uid

Resolves: #84855
Releases: master
Change-Id: I20c189b082c616590bcb2bdabff9e2f2c22a1bce
Reviewed-on: https://review.typo3.org/56793


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Susanne Moog <susanne.moog@typo3.org>
Tested-by: Susanne Moog <susanne.moog@typo3.org>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>