Docs page for writing adapters refers to old polyfill package name

[erxclau]

Describe the problem

The page for writing adapters refers to @sveltejs/kit/install-fetch but this package was renamed to @sveltejs/kit/node/polyfills.

kit/documentation/docs/25-build-and-deploy/99-writing-adapters.md

Line 40 in 67c0214

- Globally shims `fetch` to work on the target platform, if necessary. SvelteKit provides a `@sveltejs/kit/install-fetch` helper for platforms that can use `node-fetch`

Describe the proposed solution

1. Change the package name to @sveltejs/kit/node/polyfills.
2. Update language to also say that crypto is shimmed as part of the package.

Alternatives considered

No response

Importance

nice to have

Additional Information

No response

[gladimir777]

Hello, I am new to this world of contributing to open source project. And I would like give my firs contribution on solving this. Could you please asign this to me?