x/website: workspace tutorial missing code highlight

[hallazzang]

What is the URL of the page with the issue?

https://go.dev/doc/tutorial/workspaces

What is your user agent?

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.80 Safari/537.36

Screenshot

What did you do?

Visited the tutorial page.

What did you expect to see?

The module now includes both the example.com/hello module and the golang.org/x/example module.

What did you see instead?

The module now includes both the example.com/hello module and the `golang.org/x/example module.

[gopherbot]

Change https://go.dev/cl/394414 mentions this issue: _content/doc/tutorial: add missing of tutorial for workplace`