Hardcoded Node.js download URL preventing operation within corporate secured network

[yunarta]

Hi

I found that the src/tarballs/node.ts has the nodejs.org URL hardcoded in the code. I'm currently setting up secured devops with very limited network access and strict dev machine policy.

This hard coded URL preventing the developers to use our cached nodejs.org content server. I think it a better solution to allow environment variable injection to replace such URL.