Add test/mp_map_find_3

test/Jamfile

@@ -187,6 +187,7 @@ run mp_similar.cpp ;
 # map
 run mp_map_find.cpp ;
 run mp_map_find_2.cpp ;
+run mp_map_find_3.cpp ;
 run mp_map_contains.cpp ;
 run mp_map_insert.cpp ;
 run mp_map_replace.cpp ;