Update python version in containers.

[elcct]

Description of change

As in the title.

Checklist

• Has this branch been rebased on top of the current main branch?

  Explanation

  The branch should not be stale or have conflicts at the time reviews are requested.

• Is the CircleCI build passing?

General points

Other things to check

• Make sure fixtures/test_data.yaml is maintained when updating models
• Consider the admin site when making changes to models
• Use select-/prefetch-related field lists in views and search apps, and update them when fields are added
• Make sure the README is updated e.g. when adding new environment variables

See docs/CONTRIBUTING.md for more guidelines.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.63%. Comparing base (ce7c202) to head (31185e5).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5941      +/-   ##
==========================================
- Coverage   96.65%   96.63%   -0.02%     
==========================================
  Files        1070     1070              
  Lines       25262    25261       -1     
  Branches     1664     1665       +1     
==========================================
- Hits        24416    24412       -4     
- Misses        690      692       +2     
- Partials      156      157       +1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.