fix community/bug reporting guidance in docs/content/cli-commands/npm.md

[isaacs]

It's sending people to a defunct discourse instance. We should probably fix that.

[darcyclarke]

🤔 @isaacs I've chatted a bit about this with @ethomson but I think still pointing to a hub probably makes a lot of sense to direct the level/type of support &/or self-serve if possible (ie. drive to relevant docs).