test: Add failing tests for async css modules

[IanVS]

Description

This adds a failing test for #3924, to hopefully help someone who knows more than I do actually fix the bug.

Additional context

If someone can point me in the right direction I can take a crack at fixing this.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the Commit Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

[IanVS]

I think @patak-dev's post sheds some light on what might be going on here: https://patak.dev/vite/build.html#_14-vite-css-post. Specifically, this part:

This plugin will transform dynamic imports using this helper. The following

import('./async.js')

will be transpiled into

preload(
 () => import('/assets/async.js),
 ['/assets/async.css','/assets/async-dep.js']
)

It seems like what is needed is a more robust tree-walking which does not simply create a .css file for each dynamically imported asset, but rather builds up a list of files that need to be created, and then actually inject them in the correct order.

So, if we have moduleA and common which both have css modules, and might look like this:

// moduleA.js
import 'common'
import styles from 'moduleA.module.css'

// common.js
import styles from 'common.module.css'

Currently the import order is:

moduleA.js
moduleA.css
common.js
common.css

But in reality what we need is:

moduleA.js
common.js
common.css
moduleA.css

[IanVS]

The latest work on this is being done in #9278.