deps: Update supported Python versions

[a-grealish]

Proposed changes

Add support for python 3.13.

I've ran the tests locally using the 3.13rc3 and they passed

Types of changes

Please check the type of change your PR introduces:

• Release (new release request)
• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (PEP8, lint, formatting, renaming, etc)
• Refactoring (no functional changes, no api changes)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Build related changes (build process, tests runner, etc)
• Other (please describe):

Checklist

Put an x in the boxes that apply. You can also fill these out after creating
the PR. If you're unsure about any of them, don't hesitate to ask. We're here to
help! This is simply a reminder of what we are going to look for before merging
your code.

• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added documentation to https://github.com/python-social-auth/social-docs

Other information

Completed as part of DjangoLondon's HacktoberFest: djangolondon/djangolondon.github.io#188

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.72%. Comparing base (fb93814) to head (8451f95).
Report is 55 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #621   +/-   ##
=======================================
  Coverage   91.72%   91.72%           
=======================================
  Files          39       40    +1     
  Lines        1172     1185   +13     
  Branches      144       77   -67     
=======================================
+ Hits         1075     1087   +12     
- Misses         72       73    +1     
  Partials       25       25           

Flag	Coverage Δ
unittests	91.72% <ø> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

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

[nijel]

Merged, thanks for your contribution!