Add GH Actions job for publishing to PyPI and Quay.io

[juhoinkinen]

This is essentially a copy-paste from Annif: https://github.com/NatLibFi/Annif/blob/main/.github/workflows/cicd.yml

Quay.io repository does not exist yet, so this is best not to be merged at this time (I assume we do want to publist a Docker image).

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.58%. Comparing base (c0d74a6) to head (6a4d1eb).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #35   +/-   ##
=======================================
  Coverage   95.58%   95.58%           
=======================================
  Files           6        6           
  Lines          68       68           
=======================================
  Hits           65       65           
  Misses          3        3           

Flag	Coverage Δ
unittests	95.58% <ø> (ø)

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[juhoinkinen]

But this does not publish a Docker image that is built from the main branch, is that needed?