GEODE-10127: Use correct hostname in WAN with LB test

[upthewaterspout]

This test is making gateway sender side members to connect to the receiver side
through a load balance. This test used "localhost" as the hostname for
clients. That worked previously, because we were actually losing the
hostname-for-clients in the RemoteLocatorResponse, and instead sending the IP
address, due to the changes in GEODE-8955.

With the fix for GEODE-10127, we are now correctly sending the
hostname-for-clients to the gateway sender, and so
now "localhost" doesn't work. The correct hostname-for-clients is the IP
address we get from docker-compose.

Changing the test to pass the IP address instead of "localhost" to the receiver
locator, just like we do for the receivers themselves.

Re-enabling the test

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[nabarunnag]

Dan can we still use hostnames for --hostname-for-clients or it has to be IP always. Is this change just only for Docker compose case

[upthewaterspout]

@nabarunnag - In general hostname-for-clients should be a hostname, especially if you are using TLS. However, IP addresses should also work - we should just be passing whatever is in hostname-for-clients all the way to the client/gateway sender.

I'm not clear enough about networking with docker compose to know if there is a hostname we could use in this case instead of the IP address, but maybe there is something?