fix linking of @bigtest/eslint-plugin rule to docs

[dagda1]

While looking at #801 I remembered that there actually was an eslint rule for this.

The linking to the docs for the @bigtest/require-default-export is broken.

Eslint borks if it cannot find the definition.

This PR fixes it.

Maybe we should generate an eslint.json file as part of bigtest init?

[changeset-bot]

🦋 Changeset detected

Latest commit: e3c017e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@bigtest/eslint-plugin	Patch

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[github-actions]

A preview package of this pull request has been published with the tag fix-eslint-links.
You can try it out by running the following command:

$ npm install @bigtest/eslint-plugin@fix-eslint-links

or by updating your package.json to:

{
  "@bigtest/eslint-plugin": "fix-eslint-links"
}

Generated by 🚫 dangerJS against e3c017e

[dagda1]

closing in favour of #807