Add Python 3.11 to the testing

[cclauss]

https://www.python.org/downloads/release/python-3111/

[codecov]

Codecov Report

Base: 96.52% // Head: 96.52% // No change to project coverage 👍

Coverage data is based on head (2c311a1) compared to base (ecdb7fc).
Patch has no changes to coverable lines.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #41   +/-   ##
=======================================
  Coverage   96.52%   96.52%           
=======================================
  Files           5        5           
  Lines         144      144           
=======================================
  Hits          139      139           
  Misses          5        5           

Flag	Coverage Δ
unittests	96.52% <ø> (ø)

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[yhino]

Thank you for the pull request.