Enable multi test in cmake script

Author: babelouest

CMakeLists.txt

@@ -310,7 +310,7 @@ if (BUILD_HOEL_TESTING)
             set(LIBS ${LIBS} ${SUBUNIT_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT} m rt)
         endif ()
 
-        set(TESTS core)
+        set(TESTS core multi)
 
         configure_file(
                 "${CMAKE_MODULE_PATH}/CTestCustom.cmake.in"