Update submodule vtkdiff 

[Conan] Fixed hdf5 linking errors on MSVC 2019.

Remove unused functions

StationBorehole::readStratigraphyFile

GMSInterface::readSoilIDfromFile

XmlStnInterface::rapidReadFile

XMLQtInterface::insertStyleFileDefinition

getSpecificHeatCapacity()

ElementQualityMetric::getMinValue()
ElementQualityMetric::getMaxValue()

operator() (IndexType row, IndexType col)

AdsorptionReaction::getMassFraction

from MeshElementGrid.

TwoPhaseFlowWithPPMaterialProperties::getGasDensityDerivative

MeshNodesAlongPolyline::getDistOfProjNodeFromPlyStart()

ElementStatus::getActiveElementsAtNode