[MAINT] Improve Import behaviour of github_default_branch

[deiga]

Resolves #2613

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Before the change?

• Resource didn't use Context-aware functions
• Resource didn't use tflog for logging
• Missing tests for Update and Import functionality

After the change?

• Changes to use Context-aware functions
• Changes to use tflog for logging
• Adds support for repository renaming, by add repository_id field and removing ForceNew from repository

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

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[github-actions]

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