refactor: use octokit client for fetching data from REST and GraphQL endpoints

[setchy]

📝 Provide a description of the new feature

Refactor to use https://github.com/octokit/octokit.js instead of using our own github type, api clients etc

➕ Additional Information

No response

[0xdevalias]

Another potential alternative:

And react-query was mentioned a couple of times (1, 2), which is something I have worked with before and is quite nice.

Originally posted by @0xdevalias in #2284 (comment)