T29209 nnUNet caching bug fix

Summary: T29209 nnUNet caching bug is fixed. This was introduced due to the deprecation of AutoMLSegmentationWithPreviewTool class (T29185)

Test Plan: NA

Reviewers: kislinsk, O1 MITK Reviewer Group I

Reviewed By: kislinsk, O1 MITK Reviewer Group I

Subscribers: floca

Differential Revision: https://phabricator.mitk.org/D667