Update next/link API docs to mention a11y and ESLint rule.

docs/api-reference/next/link.md

@@ -91,7 +91,7 @@ export default Posts
 
 ## If the child is a custom component that wraps an `<a>` tag
 
-If the child of `Link` is a custom component that wraps an `<a>` tag, you must add `passHref` to `Link`. This is necessary if you’re using libraries like [styled-components](https://styled-components.com/). Without this, the `<a>` tag will not have the `href` attribute, which might hurt your site’s SEO.
+If the child of `Link` is a custom component that wraps an `<a>` tag, you must add `passHref` to `Link`. This is necessary if you’re using libraries like [styled-components](https://styled-components.com/). Without this, the `<a>` tag will not have the `href` attribute, which hurts your site's accessibility and might affect SEO. If you're using [ESLint](/docs/basic-features/eslint.md#eslint-plugin), there is a built-in rule `next/link-passhref` to ensure correct usage of `passHref`.
 
 ```jsx
 import Link from 'next/link'