refactor: Remove github.com/pkg/errors from Attribution.txt

Closes #4602

Already checked all the edgex repositories for this removal.

Signed-off-by: Jack Chen <jack@iotechsys.com>

Author: jackchenjc

Attribution.txt

@@ -2,9 +2,6 @@ This file contains the open source projects that are referenced by the EdgeX Fou
 As there are many Go services, this list is a union of all open source projects used by all the EdgeX Go services (found in https://github.com/edgexfoundry/edgex-go).
 Not all projects listed are used by each service.
 
-pkg/errors (BSD-2) https://github.com/pkg/errors
-https://github.com/pkg/errors/blob/master/LICENSE
-
 go-kit/kit (MIT) github.com/go-kit/kit
 https://github.com/go-kit/kit/blob/master/LICENSE