doc(github_repository): Removed misleading note about unsupported un-archiving

[ViacheslavKudinov]

Resolves #NULL

---

Before the change?

• Doc contains misleading information that it is not possible to un-archive the repo via API/provider

After the change?

• Doc has no more misleading information.
  It is not valid since Dec 2022. Blog post https://github.blog/changelog/2022-12-13-unarchive-a-repository-via-the-rest-api/ and also performed "apply" with archived = true/false.

Pull request checklist

• Schema migrations have been created if needed (example)
• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)

Does this introduce a breaking change?

Please see our docs on breaking changes to help!

• Yes
• No

---

[github-actions]

👋 Hi! Thank you for this contribution! Just to let you know, our GitHub SDK team does a round of issue and PR reviews twice a week, every Monday and Friday! We have a process in place for prioritizing and responding to your input. Because you are a part of this community please feel free to comment, add to, or pick up any issues/PRs that are labeled with Status: Up for grabs. You & others like you are the reason all of this works! So thank you & happy coding! 🚀