[TASK] Unit tests stumble on missing import

Something changed with recent phpspec/prophecy release
1.18.0 which now stumbles upon a missing namespace
import in a unit test. Import correctly.

Resolves: #102636
Relaeses: 11.5
Change-Id: If9015bbaf89bbd77bb59c084260c4bb834447ea8
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/82155


Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>