Bug: Math syntax highlighting fails when there is space before leading $

[roaldarbol]

I've found a bug in the syntax highlighting for math ($) syntax for the VS Code extension; I think it's when the leading $ directly follows another character, e.g. H$\rho$, then it fails to detect that a math syntax has been started.

Here's what it looks like in VS Code:

However, it renders just fine:

And the syntax highlighting in RStudio also picks it up just fine: