Support for OpenSSH ecdsa-sk & ed25519-sk

[Utesgui]

I would love to use my ed25519-sk-keys with the keeper ssh command.

Support was added to cryptography in March: https://github.com/pyca/cryptography/issues/10604

Screenshot with 16.11.8:

This screenshot was from 16.11.0

[sk-keeper]

The mentioned cryptography thread is about public not private key. The latest cryptography package 43.0.0 cannot load Yubikey's private key.

>>> serialization.load_ssh_private_key(private_key.encode(), password=b'...')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/skolupaev/Work/PY/sdk/lib/python3.11/site-packages/cryptography/hazmat/primitives/serialization/ssh.py", line 696, in load_ssh_private_key
    pubfields, pubdata = kformat.get_public(pubdata)
                         ^^^^^^^^^^^^^^^^^^
AttributeError: '_SSHFormatSKEd25519' object has no attribute 'get_public'. Did you mean: 'load_public'?