update debugging instructions

[Bilal-S]

Description

I had written the debugging instructions when we were still using node 4.x (4 years ago). They needed updating.

Motivation and Context

I needed to update the debugging instructions. There was no clear guide for this that I could find via a brief Google search so an update was needed to save people headaches.

How Has This Been Tested?

I use those debugging settings actively for my environment with latest version of VS Code (1.55.2)
I tested this with plain Javascript and Typescript + webpack.
For both variations I am able to open an interactive debugging session with full call stack and variables being available.

Screenshots (if appropriate):

[shawnmclean]

Someone should get this merged, good documentation.

[dherault]

Love it @Bilal-S , thanks, I remember you from way back, you're the first maintainer of this package <3