Set CONFIGURATIONS property on tests only for Xcode.

Having it in the general case disabled a large number of tests.

common/cmake_modules/GncAddTest.cmake

@@ -78,7 +78,11 @@ function(gnc_add_test _TARGET _SOURCE_FILES TEST_INCLUDE_VAR_NAME TEST_LIBS_VAR_
     )
     set_tests_properties(${_TARGET} PROPERTIES ENVIRONMENT "GNC_UNINSTALLED=YES;GNC_BUILDDIR=${CMAKE_BINARY_DIR};${ARGN}")
   else()
-    add_test(NAME ${_TARGET} COMMAND ${_TARGET} CONFIGURATIONS Debug;Release)
+    if (CMAKE_GENERATOR STREQUAL Xcode)
+      add_test(NAME ${_TARGET} COMMAND ${_TARGET} CONFIGURATIONS Debug;Release)
+    else()
+      add_test(NAME ${_TARGET} COMMAND ${_TARGET})
+    endif()
     set_tests_properties(${_TARGET} PROPERTIES ENVIRONMENT "GNC_UNINSTALLED=YES;GNC_BUILDDIR=${CMAKE_BINARY_DIR}")
   endif()
   add_dependencies(check ${_TARGET})