add a process stdin article to the Nodejs Roadmap (#7554)

src/data/roadmaps/nodejs/content/processstdin@betuntelnEMSHdatO6VPl.md

@@ -5,3 +5,4 @@ The `process.stdin` is a standard Readable stream which listens for user input a
 Visit the following resources to learn more:
 
 - [@official@Official Documentation](https://nodejs.org/api/process.html#processstdin)
+- [@article@Node.js Process stdin & stdout](https://nodecli.com/node-stdin-stdout)