Unpinning CI python versions as no longer needed

[jacobcook1995]

Description

Github actions python versions for 3.9 and 3.10 now default to 3.9.16 and 3.10.9, respectively. This means there's no longer any reason to keep the versions pinned, so I have unpinned them. (They were originally pinned to fix a weird CI edge case where a specific test would fail on macOS for python versions <3.9.16 and <3.10.9)

Type of change

• New feature (non-breaking change which adds functionality)
• Optimization (back-end change that speeds up the code)
• Bug fix (non-breaking change which fixes an issue)

Key checklist

• Make sure you've run the pre-commit checks: $ pre-commit run -a
• All tests pass: $ poetry run pytest

Further checks

• Code is commented, particularly in hard-to-understand areas
• Tests added that prove fix is effective or that feature works

[davidorme]

Sounds good! Might as well remove out of date comment too

[codecov-commenter]

Codecov Report

Merging #146 (bff89c1) into develop (39aff5a) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #146   +/-   ##
========================================
  Coverage    94.06%   94.06%           
========================================
  Files           11       11           
  Lines          472      472           
========================================
  Hits           444      444           
  Misses          28       28           

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more