Update to 2.10.4
    
    - New upstream release 2.10.4
      - Update 'camelCase' method calls against the 'threading' module to be
        'snake_case'; this and related tweaks should fix some deprecation warnings
        under Python 3.10 (GH#1838, GH#1870, GH#2028)
      - '~paramiko.pkey.PKey' instances' '__eq__' did not have the usual safety
        guard in place to ensure they were being compared to another 'PKey' object,
        causing occasional spurious 'BadHostKeyException', among other things
        (GH#1964, GH#2023, GH#2024)
      - Servers offering certificate variants of hostkey algorithms (e.g.
        'ssh-rsa-cert-v01@openssh.com') could not have their host keys verified by
        Paramiko clients, as it only ever considered non-cert key types for that
        part of connection handshaking (GH#2035)