UX review - some output blocks need a horizontal scroll and are not easy to read

[immavalls]

As reported on the community slack, we have some pages where we can only see the entire text with scrolling. And it's not easy to scroll.

E.g. https://k6.io/docs/using-k6/metrics/

https://user-images.githubusercontent.com/4788634/224300017-73be7269-cfca-413e-ba7f-392c6f2919bf.mov

Even if we zoom out, and make the text smaller, the right menu increases and the middle section does not change.