BUG: fix the path to the ruler scene file for test

Pass the Input data directory via the CMakeLists file on the command line.
Avoids the hard coded path that assumes a specific directory name for
the Slicer source code check out.

Issue #3758


git-svn-id: http://svn.slicer.org/Slicer4/trunk@23410 3bd1e089-480b-0410-8dfb-8563597acbee