razzle: Canary throwing error

🐛 Bug report

Current Behavior

Just tried npx create-razzle-app@canary my-app-razzle and when I run npm start I get the following error in the browser:

TypeError: Cannot read property 'css' of undefined

  30 |         <title>Welcome to Razzle</title>
  31 |         <meta name="viewport" content="width=device-width, initial-scale=1">
> 32 |         ${
  33 |           assets.client.css
  34 |             ? `<link rel="stylesheet" href="${assets.client.css}">`
  35 |             : ''

Expected behavior

For it to work without throwing an error

Reproducible example

Just run:

npx create-razzle-app@canary my-app-razzle && cd my-app-razzle && npm start

Your environment

Software	Version(s)
Razzle	^4.0.0-canary.7
Razzle Plugins	N/A
Node	15.0.1 (Also tried 12.16.3)
Browser	Chrome Version 86.0.4240.193
npm/Yarn	Yarn 1.22.4
Operating System	MacOS 10.15.7
TypeScript	N/A
React	^17.0.1