fix(github): fixes for assigning github role

[ReenigneArcher]

Description

A small fix for applying or removing roles to users. The previous code only worked during unit tests, bot not in production.

Also, adds a small piece of info to the readme.

Screenshot

Issues Fixed or Closed

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Dependency update (updates to dependencies)
• Documentation update (changes to documentation)
• Repository update (changes to repository files, e.g. .github/...)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated the in code docstring/documentation-blocks for new or existing methods/components

[sonarqubecloud]

Quality Gate failed

Failed conditions
1 New issue
C Maintainability Rating on New Code (required ≥ A)
1 New Code Smells (required ≤ 0)

See analysis details on SonarQube Cloud

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[codecov]

Codecov Report

Attention: Patch coverage is 80.00000% with 2 lines in your changes missing coverage. Please review.

Project coverage is 67.51%. Comparing base (630e2c5) to head (4dd5358).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
src/discord/tasks.py	80.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #375      +/-   ##
==========================================
- Coverage   67.58%   67.51%   -0.07%     
==========================================
  Files          21       21              
  Lines        1092     1096       +4     
==========================================
+ Hits          738      740       +2     
- Misses        354      356       +2     

Files with missing lines	Coverage Δ
src/discord/tasks.py	87.85% <80.00%> (-1.12%)	⬇️

[Copilot]

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (1)

src/discord/tasks.py:244

• [nitpick] The role name 'github-user' is inconsistent with the previous 'github-users'. Ensure this change is intentional and consistent across the codebase.

user_data['roles'].append('github-user')