update .clang-format

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

Change-Id: I4f51a20f469de431ee6a5ba78e3f4da39c980fab
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/src/test/callbacktest.cpp b/src/test/callbacktest.cpp
index 78736f8..f0c96e0 100644
--- a/src/test/callbacktest.cpp
+++ b/src/test/callbacktest.cpp
@@ -1,7 +1,7 @@
-#include <gtest/gtest.h>
-
 #include "generated.hpp"
 
+#include <gtest/gtest.h>
+
 using namespace phosphor::dbus::monitoring;
 
 TEST(JournalTest, Test)