Update an outdated link in README

[dav3r]

🗣 Description

This PR updates an outdated link in the README.

💭 Motivation and context

We strive for accuracy everywhere!

🧪 Testing

Visual inspection.

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• Changes are limited to a single goal - eschew scope creep!
• All relevant type-of-change labels have been added.
• I have read the CONTRIBUTING document.
• These code changes follow cisagov code standards.
• All relevant repo and/or project documentation has been updated to reflect the changes in this PR.
• All new and existing tests pass.

[Copilot]

Pull Request Overview

This PR updates an outdated GitHub repository link in the README documentation to reflect the correct organizational ownership.

• Updated repository reference from jsf9k/cyhy-commander to cisagov/cyhy-commander

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[mcdonnnj]

👴