refine include

dbms/src/Functions/LeastGreatest.h

@@ -30,16 +30,14 @@
 #include <DataTypes/IDataType.h>
 #include <Functions/FunctionHelpers.h>
 #include <Functions/IFunction.h>
+#include <Functions/StringUtil.h>
 #include <Functions/castTypeToEither.h>
 #include <Interpreters/Context.h>
 #include <common/types.h>
 #include <fmt/core.h>
 
-#include <cstddef>
 #include <type_traits>
 
-#include "StringUtil.h"
-
 namespace DB
 {
 namespace ErrorCodes