Fix bug in build dependencies
Fix bug in build dependencies

Visomics external project now properly depends on VTK external project.

This was broken by 8815d19041f994918479558edcff28f7e62005a9.

arborworkflows/Visomics,arborworkflows/Visomics,Visomics/Visomics,Visomics/Visomics,arborworkflows/Visomics,arborworkflows/Visomics,Visomics/Visomics,arborworkflows/Visomics,Visomics/Visomics,arborworkflows/Visomics,Visomics/Visomics,Visomics/Visomics