Log Message:
py-asyncssh: updated to 2.20.0

Release 2.20.0 (17 Feb 2025)

* Added support for specifying an explicit path when configuring
  agent forwarding. Thanks go to Aleksandr Ilin for pointing out
  that this options supports more than just a boolean value.

* Added support for environment variable expansion in SSH config,
  for options which support percent expansion.

* Added a new begin_auth callback in SSHClient, reporting the
  username being sent during SSH client authentication. This can be
  useful when the user is conditionally set via an SSH config file.

* Improved strict-kex interoperability during re-keying. Thanks go
  to GitHub user emeryalden for reporting this issue and helping
  to track down the source of the problem.

* Updated SFTP max_requests default to reduce memory usage when
  using large block sizes.

* Updated testing to add Python 3.13 and drop Python 3.7, avoiding
  deprecation warnings from the cryptography package.

* Fixed unit test issues under Windows, allowing unit tests to run
  on Windows on all supported versions of Python.

* Fixed a couple of issues with Python 3.14. Thanks go to Georg
  Sauthoff for initially reporting this.