Break storybook when using package which using gatsby Link component

[lwyj123]

Description

When using gatsby-theme-i18n, the storybook will breaks and show errors like below:

Module parse failed: Unexpected token (8:4)
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
| 
|   return (
>     <ul>
|       {config.map((locale) => (
|         <li key={locale.code}>
 @ /home/workspace/someproject/node_modules/gatsby-theme-i18n/index.js 5:0-59 5:0-59

After reading #5949 and https://github.com/gatsbyjs/gatsby/blob/master/docs/docs/how-to/testing/visual-testing-with-storybook.md

I was found that it's because of the gatsby-theme-i18n using Gatsby's Link component and not be compiled.

in the https://github.com/gatsbyjs/gatsby/blob/master/docs/docs/how-to/testing/visual-testing-with-storybook.md this can be fixed by using

config.module.rules[0].exclude = [/node_modules\/(?!(gatsby)\/)/]

but if some package like gatsby-theme-i18n is using the Link component, I have to change the exclude into

config.module.rules[0].exclude = [/node_modules\/(?!(gatsby|gatsby-theme-i18n)\/)/]

and I think those kind of problem should be fixed by someone or provide a better solution.

Steps to reproduce

Expected result

Actual result

Environment

[LekoArts]

We'd be happy to review a PR adding a comment above the line to say that one should include other packages there, too, if they use Gatsby Link