Fix test of ctk_list_to_string CMake function

This is a follow-up of commit of 72580ebw where the CMake function
"ctk_list_to_string" was first added.

CMake/Testing/CMakeLists.txt

@@ -13,4 +13,4 @@ endmacro()
 #
 # Add 'CMake script' Tests
 #
-add_cmakescript_test(list_to_string_test ctkListToString)
+add_cmakescript_test(ctk_list_to_string_test ctkListToString)