Keep region grower thresholds within the pixel type extrema of the reference slice

Summary:

• Keep thresholds within the pixel type extrema of the reference slice
• Fix actual output image dimensionality of ExtractSliceFilter
• Improve some method signatures of RegionGrowingTool regarding pass by const ref
• Fixes T27085

Test Plan: - Tested with the example data provided in T27085

Reviewers: O1 MITK Reviewer Group I, floca

Reviewed By: O1 MITK Reviewer Group I, floca

Maniphest Tasks: T27085

Differential Revision: https://phabricator.mitk.org/D361