GitHubUser registration

[buckyroberts]

This task will allow users to create/edit GitHubUser objects. This object is the link between a GitHub user and a thenewboston user. As background, when a GitHub user contributes to the project (a PR is merged) we will use an LLM to determine the value of that GitHub contribution and reward a thenewboston user with that amount of coins.

Related issue:

• GitHub integration

To do this, we will allow GitHub users to specify the username of a thenewboston user who they would like to receive the rewards/coins for their contributions. This user will be set as the GitHubUser.reward_recipient.

• https://github.com/thenewboston-developers/thenewboston-Backend/blob/master/thenewboston/github/models/github_user.py

GitHub users will do this by submitting a "Registration" issue. Our system will poll the GitHub API to fetch any of these issues and create/update that users GitHubUser object accordingly.

Note that the "Registration" issue template has not been created yet. It must be created as part of this task. It can be created in this repo.