doc: update `os.networkInterfaces()` example

The os.networkInterfaces() example was outdated
as the IPv6 interfaces did not include the scopeid property,
now they do.

PR-URL: https://github.com/nodejs/node/pull/25417
Fixes: https://github.com/nodejs/node/issues/25408


Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Weijia Wang <starkwang@126.com>