TT#124273 Update packaging for bullseye

- Switch to debhelper compat level 13.
- Switch to Standards-Version 4.5.1.
- Update copyright years.

Change-Id: I8c769912394cf7e2444e21a2f442d066e779e9c5

debian/control

@@ -3,11 +3,11 @@ Section: admin
 Priority: optional
 Maintainer: Sipwise Development Team <support@sipwise.com>
 Homepage: https://www.sipwise.com/
-Standards-Version: 3.9.8
+Standards-Version: 4.5.1
 Build-Depends:
  asciidoctor,
  bash-completion (>= 1:2.1-4.2~),
- debhelper-compat (= 12),
+ debhelper-compat (= 13),
  git,
  libcapture-tiny-perl,
  libclone-perl,

debian/copyright

@@ -5,7 +5,7 @@ Upstream-Contact: Sipwise Development Team <support@sipwise.com>
 Files:
  *
 Copyright:
- Copyright © 2007-2019 Sipwise GmbH, Austria
+ Copyright © 2007-2021 Sipwise GmbH, Austria
 License: GPL-3+
  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by