Make blob viewer wider for mobile

What does this MR do?

Makes the blob viewer for rich contents (e.g. .md) wider for mobile.

Are there points in the code the reviewer needs to double check?

While this MR contains media query keeping the relevant declaration, is this truly needed? If not, we can remove the declaration.

Why was this MR needed?

On a mobile device, the blob viewer for rich contents (e.g. .md) is too narrow to read. This MR improves UX for that.

Top/Bottom margins are unchanged as is before !12198 (merged).

Screenshots (if relevant)

before after
rich-blob-before rich-blob-after

Does this MR meet the acceptance criteria?

What are the relevant issue numbers?

Closes #37368 (closed)

Edited by username-removed-100770

Merge request reports