merge two onInterest callback into one

Change-Id: I82e8150239d795cb465ea2526624300590e4434c
diff --git a/tools/ndncert-client.cpp b/tools/ndncert-client.cpp
index 4b3b38a..096ceb2 100644
--- a/tools/ndncert-client.cpp
+++ b/tools/ndncert-client.cpp
@@ -18,18 +18,17 @@
  * See AUTHORS.md for complete list of ndncert authors and contributors.
  */
 
+#include "challenge-module.hpp"
+#include "client-module.hpp"
+#include "protocol-detail/info.hpp"
+#include <ndn-cxx/security/verification-helpers.hpp>
 #include <boost/asio.hpp>
 #include <boost/program_options/options_description.hpp>
 #include <boost/program_options/parsers.hpp>
 #include <boost/program_options/variables_map.hpp>
 #include <iostream>
-#include <ndn-cxx/security/verification-helpers.hpp>
 #include <string>
 
-#include "challenge-module.hpp"
-#include "client-module.hpp"
-#include "protocol-detail/info.hpp"
-
 namespace ndn {
 namespace ndncert {