Docs: add message that storybook creates node_modules in pnp

[turtle601]

Closes #25987

What I did

'yarn storybook' creates node_modules/.cache in Yarn 2 PnP project

I think the development environment can cause confusion for those developing in pnp mode.

so, i add 'yarn storybook' creates node_modules/.cache in Yarn 2 PnP project in get-started/install.md files

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[turtle601]

@jonniebigodes I'm really looking forward to your feedback on that pr

[jonniebigodes]

@turtle601 appreciate you taking the time to put together this pull request and helping us improve our documentation by adding this small but rather important piece of information that is affecting you and can affect other users as well. I left a small item for you to look into when you have a moment.

Let me know of any questions you may have so that I can unblock you and get this merged.

Looking forward to hearing from you.

Have a fantastic day.

Stay safe

[jonniebigodes]

@turtle601 we have a bit of room for improvement here, If don't mind, can you remove this callout and instead add an entry in the troubleshooting section below as follows:

#### Yarn Plug'n'Play (PnP) support with Storybook

If you've enabled Storybook in a project running on a new version of Yarn with [Plug'n'Play](https://yarnpkg.com/features/pnp) (PnP) enabled, you may notice that it will generate `node_modules` with some additional files and folders. This is a known constraint as Storybook relies on some directories (e.g., `.cache`) to store cache files and other data to improve performance and faster builds. You can safely ignore these files and folders, adjusting your `.gitignore` file to exclude them from the version control you're using.

With this, we avoid having a double aside here, adding yet another break point in the documentation and make the issue more discoverable as you can see below:

[turtle601]

@jonniebigodes Thank you so much for your feedback. :)

I saw your feedback and reflected it exactly.

I would appreciate it if you could check my PR one more time.

[jonniebigodes]

@turtle601, no need to thank you whatsoever, glad to help you! I appreciate you addressing the feedback so quickly. I've checked, and all is good on my end. I'm going to merge this once the checklist clears.

Hope you have a fantastic day.