[arccore,googletest] Supprime attribut 'SYSTEM' pour les répertoire d…

…'en-tête.

Sans cela, il n'est pas garanti d'utiliser les bons fichiers d'en-tête si
une version de 'googletest' est installée ailleurs.

arccore/extras/googletest/googletest/CMakeLists.txt

@@ -87,10 +87,10 @@ set_target_properties(gtest PROPERTIES VERSION ${GOOGLETEST_VERSION})
 cxx_library(gtest_main "${cxx_strict}" src/gtest_main.cc)
 set_target_properties(gtest_main PROPERTIES VERSION ${GOOGLETEST_VERSION})
 string(REPLACE ";" "$<SEMICOLON>" dirs "${gtest_build_include_dirs}")
-target_include_directories(gtest SYSTEM INTERFACE
+target_include_directories(gtest INTERFACE
   "$<BUILD_INTERFACE:${dirs}>"
   "$<INSTALL_INTERFACE:$<INSTALL_PREFIX>/${CMAKE_INSTALL_INCLUDEDIR}>")
-target_include_directories(gtest_main SYSTEM INTERFACE
+target_include_directories(gtest_main INTERFACE
   "$<BUILD_INTERFACE:${dirs}>"
   "$<INSTALL_INTERFACE:$<INSTALL_PREFIX>/${CMAKE_INSTALL_INCLUDEDIR}>")
 target_link_libraries(gtest_main PUBLIC gtest)