copied from OGS5

Test output files are written to ${CMAKE_BUILD_DIR}/Tests/Data.

As a WIP data files have to be in ${CMAKE_SOURCE_DIR}../data

This should also fix local VTK build with OGS_USE_PETSC.

Boost, VTK, Eigen
Closes #892.

This is the used by ExternalProjectVTK / -Catalyst.cmake

This will be used instead of the custom catalyst vtk editions making
it much more easier to add new vtk libraries to the automatic build,
see #869.

Catalyst will be used in the future but just for in-situ vis configs.

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