WIP: Switching to using Bagbutik

[orj]

Prior to this PR the project used AppStoreConnect_Swift_SDK for all API interactions.

This PR refactors the project to use Bagbutik instead.

Bagbutik supports Linux and provides a better (async/await) based API and is generated from the AppStoreConnect Swagger spec.

📝 Summary of Changes

Changes proposed in this pull request:

• Introduce Bagbutik
• TODO: Remove all references to AppStoreConnect_Swift_SDK

🧐🗒 Reviewer Notes

💁 Example

TODO...

🔨 How To Test

TODO...