Move BOOST_CONCEPT_ASSERT to unit tests where possible

Change-Id: I0c6ae494eb7be4ab2ff422ba6d866ead9e75f4eb
diff --git a/tests/unit/lp/fields.t.cpp b/tests/unit/lp/fields.t.cpp
new file mode 100644
index 0000000..e828051
--- /dev/null
+++ b/tests/unit/lp/fields.t.cpp
@@ -0,0 +1,45 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2013-2023 Regents of the University of California.
+ *
+ * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
+ *
+ * ndn-cxx library is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-cxx library is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+ *
+ * You should have received copies of the GNU General Public License and GNU Lesser
+ * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
+ */
+
+#include "ndn-cxx/lp/fields.hpp"
+
+namespace ndn {
+namespace lp {
+namespace tests {
+
+BOOST_CONCEPT_ASSERT((Field<FragmentField>));
+BOOST_CONCEPT_ASSERT((Field<SequenceField>));
+BOOST_CONCEPT_ASSERT((Field<FragIndexField>));
+BOOST_CONCEPT_ASSERT((Field<FragCountField>));
+BOOST_CONCEPT_ASSERT((Field<PitTokenField>));
+BOOST_CONCEPT_ASSERT((Field<NackField>));
+BOOST_CONCEPT_ASSERT((Field<IncomingFaceIdField>));
+BOOST_CONCEPT_ASSERT((Field<NextHopFaceIdField>));
+BOOST_CONCEPT_ASSERT((Field<CachePolicyField>));
+BOOST_CONCEPT_ASSERT((Field<CongestionMarkField>));
+BOOST_CONCEPT_ASSERT((Field<AckField>));
+BOOST_CONCEPT_ASSERT((Field<TxSequenceField>));
+BOOST_CONCEPT_ASSERT((Field<NonDiscoveryField>));
+BOOST_CONCEPT_ASSERT((Field<PrefixAnnouncementField>));
+
+} // namespace tests
+} // namespace lp
+} // namespace ndn