feat(github): add github integration

[ReenigneArcher]

Description

This PR aims to more tightly integrate GitHub with our discord bot.

Main features to add

1. Assign roles based on GitHub sponsorship status
2. Assign dev-user role based on GitHub account... (whether it exists, has contributed, or something along those lines)

TODO:

• Persist OAuth status?
• Periodically check GitHub user's for sponsor status, and add user to sponsor roles, or revoke accordingly
• Callback to public URL
• Possible to hide disocrd bot IP?
• Improved SSL certs
• Update dockerfile
• Update readme/docs
• Add/update unit tests
  • Unit tests hang on unix due to async nonsense
  • Unit tests do not post comment even though tests pass (on Windows)
• Add GitHub username to user_info_commmand

Screenshot

Issues Fixed or Closed

• Resolves Receive and process external webhooks #66

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