update .clang-format header inclusion order

Added the header inclusion order to the .clang-format file generated
these changes.

Change-Id: Ia31b21d7ea451cac0309828006bc17c27cbd5bd5
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/test/utility/type_traits.cpp b/test/utility/type_traits.cpp
index 1a411f7..6e15201 100644
--- a/test/utility/type_traits.cpp
+++ b/test/utility/type_traits.cpp
@@ -1,7 +1,8 @@
-#include <gtest/gtest.h>
 #include <sdbusplus/utility/type_traits.hpp>
 #include <type_traits>
 
+#include <gtest/gtest.h>
+
 namespace
 {