[BUGFIX] Fix typo in CacheManager

By fixing a typo in the CacheManager empty tag arrays
are detected and intercepted.

Resolves: #79236
Releases: master
Change-Id: I67fccda3755274f3334f0916d26beabbb28b8eb4
Reviewed-on: https://review.typo3.org/51234


Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Mona Muzaffar <mona.muzaffar@gmx.de>
Tested-by: Mona Muzaffar <mona.muzaffar@gmx.de>
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>