message: Add api refrence to useEntity
diff: @@ -31,7 +31,7 @@ Creating the plugin...
  ### Reading entities from within your plugin
  You can access the currently selected entity using the backstage api
  -`useEntity`. For example,
  +[`useEntity`](../reference/plugin-catalog-react.useentity.md). For example,
  ```tsx
  import { useEntity } from '@backstage/plugin-catalog-react';
  