COMP: support using TestingHelper for OTB_TESTING_STANDALONE mode

Testing/CMakeLists.txt

Testing/Code/ApplicationEngine/CMakeLists.txt

Testing/Code/BasicFilters/CMakeLists.txt

Testing/Code/ChangeDetection/CMakeLists.txt

Testing/Code/Common/CMakeLists.txt

Testing/Code/DisparityMap/CMakeLists.txt

Testing/Code/FeatureExtraction/CMakeLists.txt

Testing/Code/Fusion/CMakeLists.txt

Testing/Code/Fuzzy/CMakeLists.txt

Testing/Code/GeospatialAnalysis/CMakeLists.txt

Testing/Code/Gui/CMakeLists.txt

Testing/Code/Hyperspectral/CMakeLists.txt

Testing/Code/IO/CMakeLists.txt

Testing/Code/Learning/CMakeLists.txt

Testing/Code/Markov/CMakeLists.txt

Testing/Code/MultiScale/CMakeLists.txt

Testing/Code/MultiTemporal/CMakeLists.txt

Testing/Code/OBIA/CMakeLists.txt

Testing/Code/ObjectDetection/CMakeLists.txt

Testing/Code/Projections/CMakeLists.txt