Cleanup

Not really need here and caused some warnings to appear
in the unity builds.

Warning were of type:
MaterialLib/FractureModels/Coulomb.cpp:182:38: warning: ‘MaterialLib::Fracture::Coulomb::Coulomb<DisplacementDim>::computeConstitutiveRelation(double, const ParameterLib::SpatialPosition&, double, Eigen::Ref<const Eigen::Matrix<double, -1, 1> >, Eigen::Ref<const Eigen::Matrix<double, -1, 1> >, Eigen::Ref<const Eigen::Matrix<double, -1, 1> >, Eigen::Ref<const Eigen::Matrix<double, -1, 1> >, Eigen::Ref<Eigen::Matrix<double, -1, 1> >, Eigen::Ref<Eigen::Matrix<double, -1, -1> >, typename MaterialLib::Fracture::FractureModelBase<DisplacementDim>::MaterialStateVariables&) [with int DisplacementDim = 3; typename MaterialLib::Fracture::FractureModelBase<DisplacementDim>::MaterialStateVariables = MaterialLib::Fracture::FractureModelBase<3>::MaterialStateVariables]::<lambda(const ResidualVectorType&)>’ has a field ‘MaterialLib::Fracture::Coulomb::Coulomb<DisplacementDim>::computeConstitutiveRelation(double, const ParameterLib::SpatialPosition&, double, Eigen::Ref<const Eigen::Matrix<double, -1, 1> >, Eigen::Ref<const Eigen::Matrix<double, -1, 1> >, Eigen::Ref<const Eigen::Matrix<double, -1, 1> >, Eigen::Ref<const Eigen::Matrix<double, -1, 1> >, Eigen::Ref<Eigen::Matrix<double, -1, 1> >, Eigen::Ref<Eigen::Matrix<double, -1, -1> >, typename MaterialLib::Fracture::FractureModelBase<DisplacementDim>::MaterialStateVariables&) [with int DisplacementDim = 3; typename MaterialLib::Fracture::FractureModelBase<DisplacementDim>::MaterialStateVariables = MaterialLib::Fracture::FractureModelBase<3>::MaterialStateVariables]::<lambda(const ResidualVectorType&)>::<mat capture>’ whose type uses the anonymous namespace [-Wsubobject-linkage]
  182 |         auto const update_solution = [&](ResidualVectorType const& increment) {

Saves ca. 35 unneeded includes (out of 260)
and 25s of compilation time (out of 149s).

Add prism element type to structure mesh generator tool.

Add bulk element mappings for triangles.

Clang-tidy cleanups.

This is necessary because of a doxygen bug in
documenting overloaded functions.

Fix cppcoreguidelines-pro-type-member-init.

Fix cppcoreguidelines-pro-type-member-init.

Fix google-readability-braces-around-statements.

Fix warning cppcoreguidelines-pro-type-member-init.

Van Genuchten capillary pressure saturation

Thanks to @Scinopode for reporting.

Cleanup