[PL] Python BHE BC; Avoid implicity conversion.

Avoid implicit narrowing conversion from Eigen::IndexType
to an int.

warning C4244: 'initializing': conversion from 'const _Ty' to '_Objty', possible loss of data
807         with
808         [
809             _Ty=MathLib::EigenVector::IndexType
810         ]
811         and
812         [
813             _Objty=int
814         ]

ProcessLib/BoundaryCondition/Python/BHEInflowPythonBoundaryCondition.h

@@ -41,7 +41,7 @@ public:
           _bhe(bhe),
           _py_bc_object(py_bc_object)
     {
-        const auto g_idx_T_out = in_out_global_indices.second;
+        const auto g_idx_T_out = static_cast<int>(in_out_global_indices.second);
 
         // store the bc node ids to BHE network dataframe
         std::get<3>(_py_bc_object.dataframe_network).emplace_back(g_idx_T_out);