Pro Custodibus Agent 1.4.4

Added
-----

* Make app UI URL customizable (used in WireGuard config file comments).
  Customize by adding an `App` setting to the procustodibus.conf file;
  eg:
  ```
  App = https://procustodibus.example.com
  ```
* Tests for Python 3.12.
* Installer tests for Alpine 3.19, Fedora 39, and Ubuntu 23.10.

Fixed
-----

* When removing a `[Peer]` section from a WireGuard config file, also
  remove any comments directly above the section.

Changed
-------

* Added `nftables` package to base WireGuard docker image.
  To use with podman, see the end of the "Kernel Module Loading" section
  in the following article for the updated list of nftables kernel
  modules that may need to be pre-loaded:

  https://www.procustodibus.com/blog/2022/10/wireguard-in-podman/#kernel-module-loading