tests: namespace cleanup

Change-Id: Ic34a8d5330759db6ff037479dc29dc148095a256
diff --git a/tests/unit-tests/test-multiple-user.cpp b/tests/unit-tests/test-multiple-user.cpp
index 83d00da..ad1d2ed 100644
--- a/tests/unit-tests/test-multiple-user.cpp
+++ b/tests/unit-tests/test-multiple-user.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
 /*
- * Copyright (c) 2012-2023 University of California, Los Angeles
+ * Copyright (c) 2012-2024 University of California, Los Angeles
  *
  * This file is part of ChronoSync, synchronization library for distributed realtime
  * applications for NDN.
@@ -21,8 +21,7 @@
 
 #include "tests/boost-test.hpp"
 
-namespace chronosync {
-namespace test {
+namespace chronosync::tests {
 
 class Handler
 {
@@ -102,5 +101,4 @@
 
 BOOST_AUTO_TEST_SUITE_END()
 
-} // namespace test
-} // namespace chronosync
+} // namespace chronosync::tests