[extractor/cbc] Fix upgrade required

[makew0rld]

IMPORTANT: PRs without the template will be CLOSED

Description of your pull request and other information

A temporary fix is obtained by allowed the upgrade status code to be accepted. The API still returns the information we want, just with the header status code 426 because clients should be updating to a newer API version with different paths.

Fixes #7477

Template

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• At least skimmed through contributing guidelines including yt-dlp coding conventions
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• Fix or improvement to an extractor (Make sure to add/update tests)
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• Core bug fix/improvement
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Copilot Summary

🤖 Generated by Copilot at a4dd709

Summary

🛠️🆙🚨

Fix CBC extractor by handling 426 status code. Update cbc.py to raise an ExtractorError when the CBC API requires a newer version.

_new_claims_token
Handles 426 error
Autumn of the API

Walkthrough

• Fix CBC extractor by handling 426 status code and updating API version (link, F0L