[BUG] leave the httpevent outputServers as it is

[YifengMao]

Describe the bug
hostname will be automatically converted to ip addr in setup() api:
` self.discovered_servers = []
for host in hosts:
try:
formatted_hostname = socket.gethostbyname(host)
if new_key:
key = create_new_hec_key(formatted_hostname)
except (socket.gaierror, requests.ConnectionError):
self.logger.warning('failed to reach %s, skip...' % host)
continue
except (ValueError, KeyError):
self.logger.warning('failed to setup hec token for %s, skip...' % host)
continue

            self.discovered_servers.append({"protocol": str(protocol), "address": str(formatted_hostname), "port": str(hec_port), "key": str(key)})

`
if i have a dynamic provisioned splunk behind a fixed FQDN, i don't have any workarounds to make it work. Is it possible to leave the host as it is in setup stage?

[jcmia1]

I am seeing issues reported in this forum discussions: https://forums.aws.amazon.com/message.jspa?messageID=714343. This means in-flight events could be sending to a wrong destination IF the IPs change. I have already experienced this in our labs.