[BUGFIX] Fix failing test

A superflous function was used, that does not exist in Extbase 1.3.

Change-Id: Ib25d21c53afc47a36fe44e4317abd78e736dc115
Resolves: #54280
Releases: 4.5
Reviewed-on: https://review.typo3.org/26040
Reviewed-by: Jigal van Hemert
Tested-by: Jigal van Hemert
Reviewed-by: Stefan Neufeind
Tested-by: Stefan Neufeind