Migrate to C++17 and misc code cleanups

Change-Id: I6b63385c92361a7ef5803d2bfd00f39c77e88d34
diff --git a/tests/unit/repo-command-parameter.cpp b/tests/unit/repo-command-parameter.cpp
index f01832a..94429fe 100644
--- a/tests/unit/repo-command-parameter.cpp
+++ b/tests/unit/repo-command-parameter.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2018, Regents of the University of California.
+ * Copyright (c) 2014-2022, Regents of the University of California.
  *
  * This file is part of NDN repo-ng (Next generation of NDN repository).
  * See AUTHORS.md for complete list of repo-ng authors and contributors.
@@ -18,17 +18,14 @@
  */
 
 #include "repo-command-parameter.hpp"
-
 #include "common.hpp"
 
-#include <ndn-cxx/encoding/block.hpp>
 #include <ndn-cxx/encoding/block-helpers.hpp>
 
 #include <boost/lexical_cast.hpp>
 #include <boost/test/unit_test.hpp>
 
-namespace repo {
-namespace tests {
+namespace repo::tests {
 
 BOOST_AUTO_TEST_SUITE(RepoCommandParameter)
 
@@ -58,5 +55,4 @@
 
 BOOST_AUTO_TEST_SUITE_END()
 
-} // namespace tests
-} // namespace repo
+} // namespace repo::tests