test: fix test-net-* error code check for getaddrinfo(3)

Replace '...' as invalid hostname with '***', which will give a more
consisten error message on different systems. The hostname '...' returns
EAI_AGAIN on musl libc and EAI_NONAME on most other systems.

By changing the testcase we get same restult on all known platforms.

PR-URL: https://github.com/nodejs/node/pull/5099


Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Rod Vagg <rod@vagg.org>