VOL-4925 - Build and release components.

Misc
----
  o Bulk update copyright notice to 2023.

Makefile
makefiles/*
-----------
  o Replace rm -rf with make builtin $(RM) -r
  o Move help target into makefiles/help.

go.mod
go.sum
------
  o Update opencord dependencies to the latest released versions.

Change-Id: I56eba94ddf878b318277b9e46a98053fae36ffcf
diff --git a/internal/pkg/core/openolt_test.go b/internal/pkg/core/openolt_test.go
index f909128..575ce64 100644
--- a/internal/pkg/core/openolt_test.go
+++ b/internal/pkg/core/openolt_test.go
@@ -1,5 +1,5 @@
 /*
- * Copyright 2018-present Open Networking Foundation
+ * Copyright 2018-2023 Open Networking Foundation (ONF) and the ONF Contributors
 
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.