Reduce unnecessary inclusions of `detail/common.hpp`

Change-Id: I79dcd05297594ccd4489d8cddddb879655373cc0
diff --git a/tests/unit/clock-fixture.cpp b/tests/unit/clock-fixture.cpp
index 0efe19c..07afd85 100644
--- a/tests/unit/clock-fixture.cpp
+++ b/tests/unit/clock-fixture.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2013-2023 Regents of the University of California.
+ * Copyright (c) 2013-2024 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -24,8 +24,8 @@
 namespace ndn::tests {
 
 ClockFixture::ClockFixture()
-  : m_steadyClock(make_shared<time::UnitTestSteadyClock>())
-  , m_systemClock(make_shared<time::UnitTestSystemClock>())
+  : m_steadyClock(std::make_shared<time::UnitTestSteadyClock>())
+  , m_systemClock(std::make_shared<time::UnitTestSystemClock>())
 {
   time::setCustomClocks(m_steadyClock, m_systemClock);
 }