[cmake] Symbol OGS_USE_PYTHON is not required on ProcessLibBoundaryConditionAndSourceTermPython.

ProcessLib/BoundaryConditionAndSourceTerm/Python/CMakeLists.txt

@@ -23,8 +23,6 @@ target_compile_definitions(
            $<$<BOOL:${OGS_ENABLE_ELEMENT_CUBOID}>:OGS_ENABLE_ELEMENT_CUBOID>
            $<$<BOOL:${OGS_ENABLE_ELEMENT_PRISM}>:OGS_ENABLE_ELEMENT_PRISM>
            $<$<BOOL:${OGS_ENABLE_ELEMENT_PYRAMID}>:OGS_ENABLE_ELEMENT_PYRAMID>
-    PRIVATE
-        OGS_USE_PYTHON
 )
 
 target_link_libraries(