fix: resolve broken links in cookbook

[thisisjoshford]

Pre-flight checklist

• I have read the Contributing Guidelines on pull requests.
• Commit messages follow the conventional commits spec
• If this is a code change: I have written unit tests.
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• If this is a new API or substantial change: the PR has an accompanying issue (closes #0000) and the maintainers have approved on my working plan.

Motivation

Cookbook links in README were all broken due to a file extension mistake (.js instead of .ts)

Test Plan

Related issues/PRs

[changeset-bot]

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Latest commit: f1ec117

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