Slim down `common.hpp`

Change-Id: Ic9843a1b9ffc5b5b1fa6062c8250ba28c6aaa898
diff --git a/tests/ping/client/statistics-collector.t.cpp b/tests/ping/client/statistics-collector.t.cpp
index 5d3e0d3..30f2c4b 100644
--- a/tests/ping/client/statistics-collector.t.cpp
+++ b/tests/ping/client/statistics-collector.t.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2023,  Arizona Board of Regents.
+ * Copyright (c) 2014-2024,  Arizona Board of Regents.
  *
  * This file is part of ndn-tools (Named Data Networking Essential Tools).
  * See AUTHORS.md for complete list of ndn-tools authors and contributors.
@@ -22,6 +22,7 @@
 #include "tests/test-common.hpp"
 
 #include <ndn-cxx/util/dummy-client-face.hpp>
+#include <cmath>
 
 namespace ndn::ping::client::tests {