fix: change default APM server_url to 'http://127.0.0.1:8200' to avoi…

…d IPv6 ambiguity

The APM agent won't *require* this change, because in the referenced
change it will be adding the same default on its end.

Refs: elastic/apm-agent-nodejs#3049

index.js

@@ -232,7 +232,7 @@ Client.prototype.config = function (opts) {
   if (!this._conf.size && this._conf.size !== 0) this._conf.size = 750 * 1024
   if (!this._conf.time && this._conf.time !== 0) this._conf.time = 10000
   if (!this._conf.serverTimeout && this._conf.serverTimeout !== 0) this._conf.serverTimeout = 15000
-  if (!this._conf.serverUrl) this._conf.serverUrl = 'http://localhost:8200'
+  if (!this._conf.serverUrl) this._conf.serverUrl = 'http://127.0.0.1:8200'
   if (!this._conf.hostname) this._conf.hostname = hostname
   if (!this._conf.environment) this._conf.environment = process.env.NODE_ENV || 'development'
   if (!this._conf.truncateKeywordsAt) this._conf.truncateKeywordsAt = 1024
@@ -987,7 +987,7 @@ function getChoppedStreamHandler (client, onerror) {
       //
       // The HTTP keep-alive agent will unref sockets when unused, and ref them
       // during a request. Given that the normal makeIntakeRequest behaviour
-      // is to keep a request open for up to 10s (`apiRequestTimeout`), we must
+      // is to keep a request open for up to 10s (`apiRequestTime`), we must
       // manually unref the socket.
       //
       // The exception is when in a Lambda environment, where we *do* want to