Add support for Python 3.11

[hugovk]

Like #268.

[codecov]

Codecov Report

Merging #307 (94f0ab3) into main (70d1163) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #307   +/-   ##
=======================================
  Coverage   99.48%   99.48%           
=======================================
  Files           8        8           
  Lines         778      778           
=======================================
  Hits          774      774           
  Misses          4        4           

Flag	Coverage Δ
GHA_Ubuntu	99.48% <ø> (ø)
GHA_Windows	99.48% <ø> (ø)
GHA_macOS	99.48% <ø> (ø)

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