Add notification about npm output

[SleeplessByte]

npm outputs very scary looking "vulnerability" messaging, multiple times, all the way down the dependency tree, when there is a CVE for such dependency. About 100% of the time, these warnings are not applicable to the use-case of this track and can safely be ignored.

Add a message about this in the instructions to avert issues like exercism/exercism#5212.

[iHiD]

Is there any silent mode or piping stderr or anything that we could incorporate into the command?

[SleeplessByte]

Yeah -- but that would hide stuff to help them resolve their configuration / local system.

[tejasbubane]

We can ask npm not to run audit after npm install. Using npm-config: https://docs.npmjs.com/misc/config#audit

[chiptus]

Maybe fix the vulnerabilities?

[tejasbubane]

@chiptus

Maybe fix the vulnerabilities?

1. They come up pretty often
2. Students cannot always get the newer files: (JS Track)Problem with npm install for scrabble-score problem exercism#5212 (comment)

[SleeplessByte]

And they're usually not vulnerabilities in the sense that there is an attack surface/vector.