Add missing license header

Orthtree/include/CGAL/Orthtree/Nearest_neighbors.h

@@ -1,4 +1,13 @@
-// todo: license
+// Copyright (c) 2023 INRIA
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
+//
+// Author(s)     : Jackson Campolattaro
 
 #ifndef ORTHTREE_EXAMPLES_NEAREST_NEIGHBORS_H
 #define ORTHTREE_EXAMPLES_NEAREST_NEIGHBORS_H