Refactor link-checker to work with json

[zeguillen]

Pull Request

What does this PR do?

• Fixes link-checker for json files

PR checklist

Please check if your PR fulfills the following requirements:

• Does this PR fix an existing issue, or have you listed the changes applied in the PR description (and why they are needed)?
• Have you read the contributing guidelines?
• Have you made sure that the title is accurate and descriptive of the changes?

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[meili-bot]

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[guimachiavelli]

LGTM!