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.

test/parallel/test-net-better-error-messages-port-hostname.js

@@ -3,12 +3,12 @@ var common = require('../common');
 var net = require('net');
 var assert = require('assert');
 
-var c = net.createConnection(common.PORT, '...');
+var c = net.createConnection(common.PORT, '***');
 
 c.on('connect', common.fail);
 
 c.on('error', common.mustCall(function(e) {
   assert.equal(e.code, 'ENOTFOUND');
   assert.equal(e.port, common.PORT);
-  assert.equal(e.hostname, '...');
+  assert.equal(e.hostname, '***');
 }));

test/parallel/test-net-connect-immediate-finish.js

@@ -3,14 +3,14 @@ const common = require('../common');
 const assert = require('assert');
 const net = require('net');
 
-const client = net.connect({host: '...', port: common.PORT});
+const client = net.connect({host: '***', port: common.PORT});
 
 client.once('error', common.mustCall(function(err) {
   assert(err);
   assert.strictEqual(err.code, err.errno);
   assert.strictEqual(err.code, 'ENOTFOUND');
   assert.strictEqual(err.host, err.hostname);
-  assert.strictEqual(err.host, '...');
+  assert.strictEqual(err.host, '***');
   assert.strictEqual(err.syscall, 'getaddrinfo');
 }));