Update project template cruft

[smkent]

Applied updates from upstream project template commits:

9a783dd...3047ece

*   3047ece Merge pull request #123 from smkent/ci
|\  
| * f86d59f Remove Python 3.9 from cookie-python CI config
|/  
*   502e129 Merge pull request #122 from smkent/pytest
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| * e81361b Migrate pytest config in `pyproject.toml` to modern format
|/  
* b7b8e41 Merge pull request #121 from smkent/manage-cookie
* 90d599a Update project template cruft, dependencies

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.86%. Comparing base (3047ece) to head (6bceaa0).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #124   +/-   ##
=======================================
  Coverage   84.86%   84.86%           
=======================================
  Files           8        8           
  Lines         304      304           
=======================================
  Hits          258      258           
  Misses         46       46           

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