update license to match our other examples.
// This file is part of JavaSMT,
-// JavaSMT is an API wrapper for a collection of SMT solvers.:
+// an API wrapper for a collection of SMT solvers:
// https://github.com/sosy-lab/java-smt
//
-// Copyright (C) 2007-2020 Dirk Beyer
// SPDX-FileCopyrightText: 2020 Dirk Beyer <https://www.sosy-lab.org>
//
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: Unlicense OR Apache-2.0 OR MIT
package org.sosy_lab.java_smt.example;
