feat: Contributor backend 49

[SKairinos]

This change is 

[faucomte97]

Reviewed 7 of 7 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @SKairinos)

[codecov]

Codecov Report

Attention: Patch coverage is 74.57627% with 30 lines in your changes missing coverage. Please review.

Project coverage is 68.61%. Comparing base (20103c6) to head (1cb057e).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...fe/permissions/auth_header_is_github_oidc_token.py	60.29%	27 Missing ⚠️
codeforlife/tests/permission.py	93.75%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #164      +/-   ##
==========================================
+ Coverage   68.38%   68.61%   +0.23%     
==========================================
  Files         124      126       +2     
  Lines        2976     3094     +118     
==========================================
+ Hits         2035     2123      +88     
- Misses        941      971      +30     

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[faucomte97]

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @SKairinos)