[Code Block] Code block rendering issue in Set Up a Testing Environment handbook page

The code block on the [Set Up a Testing Environment](https://make.wordpress.org/test/handbook/get-setup-for-testing/set-up-a-testing-environment/)" handbook page is not displaying correctly. It appears that the formatting or rendering is broken.

<img width="1783" height="832" alt="Image" src="https://github.com/user-attachments/assets/39b772fd-8893-4d94-ac24-4173ef773be4" />