[PL/ST] Use bulk_mesh_dimension instead of dimension of the source term mesh.

At the moment the most important difference
between line source term and the volumetric source
term is the handling of the dimension. In order to
unify the implementations further the
bulk_mesh_dimension is used instead of the
dimension of the source_term_mesh.

ProcessLib/SourceTerms/VolumetricSourceTerm.cpp

@@ -15,7 +15,7 @@
 namespace ProcessLib
 {
 VolumetricSourceTerm::VolumetricSourceTerm(
-    MeshLib::Mesh const& source_term_mesh,
+    unsigned const bulk_mesh_dimension, MeshLib::Mesh const& source_term_mesh,
     std::unique_ptr<NumLib::LocalToGlobalIndexMap> source_term_dof_table,
     unsigned const integration_order, unsigned const shapefunction_order,
     ParameterLib::Parameter<double> const& source_term_parameter)
@@ -23,7 +23,7 @@ VolumetricSourceTerm::VolumetricSourceTerm(
       _source_term_parameter(source_term_parameter)
 {
     ProcessLib::createLocalAssemblers<VolumetricSourceTermLocalAssembler>(
-        source_term_mesh.getDimension(), source_term_mesh.getElements(),
+        bulk_mesh_dimension, source_term_mesh.getElements(),
         *_source_term_dof_table, shapefunction_order, _local_assemblers,
         source_term_mesh.isAxiallySymmetric(), integration_order,
         _source_term_parameter);

ProcessLib/SourceTerms/VolumetricSourceTerm.h

@@ -22,6 +22,7 @@ class VolumetricSourceTerm final : public SourceTerm
 {
 public:
     VolumetricSourceTerm(
+        unsigned const bulk_mesh_dimension,
         MeshLib::Mesh const& source_term_mesh,
         std::unique_ptr<NumLib::LocalToGlobalIndexMap> source_term_dof_table,
         unsigned const integration_order, unsigned const shapefunction_order,