Don't pass VS Code editor font size to DevTools #5406

We pass the editor font size to DevTools with the intention of making things larger for users that might prefer/require larger fonts. However in practice, this results in much larger DevTools than expected and since the editor font size applies only to the editor, users are likely to instead zoom the whole VS Code window (which also includes DevTools) if they would like everything bigger.

There's some discussion in flutter/devtools#8243, but the TL;DR is that we should remove this and allow DevTools to appear standard size by default, and scale with the zoom settings, not the editor font.