Add an e2e test for the css serving issue (#81683)
## Add a regression test for when a not-found component depends on css and triggers a bug in turbopack
To correctly serve js and css resources during server side rendering we construct a client manifest that lists all the server components and their required resources. Turbopack has a bug where we fail to collect css that is used by the page if it is also used by a not-found page (and other error handlers as well).
When a not-found component is present all pages pages implicitly depend on this module and depend on it as an early dependency of the generated `app-page.js` file. This means if a `not-found.js` file (or a global error file) would happen to depend on the same css as a normal component we would associate it as a client-reference of that component instead of any other. Then on a server side render we would simply omit it. This PR adds a regression test for this issue.
See #77861 and #79535
