Allow copyright years in the 202[0-9] range

Change-Id: I141670f27a904b3ed23e360cda7265845a9ccc89
diff --git a/tools/build/conf/src/main/resources/onos/onos-java.header b/tools/build/conf/src/main/resources/onos/onos-java.header
index 33bcacd..3de16d3 100644
--- a/tools/build/conf/src/main/resources/onos/onos-java.header
+++ b/tools/build/conf/src/main/resources/onos/onos-java.header
@@ -1,4 +1,4 @@
 /*
- * Copyright 201[0-9].* Open Networking Foundation
+ * Copyright 20[1-2][0-9].* Open Networking Foundation
  *
  * Licensed under the Apache License, Version 2.0 \(the "License"\);