Revert "Update VisomicsData external project so that branch xcorrel-flip is used"
Revert "Update VisomicsData external project so that branch xcorrel-flip is used"

This reverts commit 2f241ccefce6364bce31f935175b15f83f64532a.

We will have a unique branch in 'next' to change GIT_TAG in
CMakeExternals/VisomicsData.cmake, rather than introducing a seperate
commit to every topic branch.

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