py-cheroot: updated to 6.1.2

v6.1.2
- :issue:81: Fix regression introduced by :pr:80.
  * Restore :py:attr:storing bound socket
    <cheroot.server.HTTPServer.bind_addr> in Windows broken by use of
    :py:obj:socket.AF_UNIX

v6.1.1
- :pr:80: Fix regression introduced by :commit:68a5769.
  * Get back support for :py:obj:socket.AF_UNIX in stored bound address in
    :py:attr:cheroot.server.HTTPServer.bind_addr

(adam)