BUG: Fix ExecutionModelTour input mrml scene

As explained in in-lined comment associated with r23587,
readWriteAsTransformToParent is not present anymore in current scenes,
because transforms are always written as TransformFromParent

git-svn-id: http://svn.slicer.org/Slicer4/trunk@23589 3bd1e089-480b-0410-8dfb-8563597acbee