[Bug]: React is not defined in newly scaffolded React Checkout UI Extension

[jamesvidler]

Please confirm that you have:

• Searched existing issues to see if your issue is a duplicate. (If you’ve found a duplicate issue, feel free to add additional information in a comment on it.)
• Reproduced the issue in the latest CLI version.

In which of these areas are you experiencing a problem?

Extension

Expected behavior

With a newly scaffolded/generated React/TypeScriptReact checkout ui extension, running yarn dev should allow you to preview your development store with the extension rendered without error.

Actual behavior

The extension does not render and you get the console error React is not defined.

Stack trace

No response

Reproduction steps

1. Ensure you are running the Go version of the extension CLI.
2. yarn create @shopify/app --template node
3. cd <name-of-app>
4. yarn generate extension, select "JavasScript React"
5. yarn dev
6. Click the checkout preview link for your extension.
7. Open web developer tools and note the console error regarding React is not defined.

Operating System

Mac OS Montery

Shopify CLI version (check your project's package.json if you're not sure)

3.16.2

Shell

zsh

Node version (run node -v if you're not sure)

v18.7.0

What language and version are you using in your application?

No response

[jamesvidler]

Related to this change #577.