WRG: avoid unreferenced local variable when itk::ExceptionObject is not used in DS test

Modules/Learning/DempsterShafer/include/otbStandardDSCostFunction.hxx

@@ -80,7 +80,7 @@ typename StandardDSCostFunction<TDSValidationFilter>
     {
     internalFunctionGT->SetDescriptorModels(descModel);
     }
-  catch ( itk::ExceptionObject & err )
+  catch ( itk::ExceptionObject & )
     {
     return 1;
     }