test: Stop using network in 404-private-registry test
test: Stop using network in 404-private-registry test

PR-URL: https://github.com/npm/npm/pull/13397
Credit: da39a3ee5e6b4b0d3255bfef95601890afd80709@iarna
Reviewed-By: da39a3ee5e6b4b0d3255bfef95601890afd80709@othiym23

evocateur/npm,evocateur/npm,chadnickbok/npm,evocateur/npm,chadnickbok/npm,chadnickbok/npm