clang-format: update to latest from docs repo

The openbmc/docs/style/cpp/.clang-format has been updated to support
clang-format10, take this opportunity to update it in this repo.

Change-Id: I9e6b9853bf4cd7399b1ae504ea3be5093d763fee
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/item_updater_helper.hpp b/item_updater_helper.hpp
index 13b98da..2aeeb23 100644
--- a/item_updater_helper.hpp
+++ b/item_updater_helper.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <sdbusplus/bus.hpp>
+
 #include <string>
 
 namespace phosphor