CAN PROVIDE THE CONFIGURATION OF DNS

## Why you need it?
I have tried to config the dynamic domain name to replace the configuration of "server ip"，but it didn't work.
My network's environment cannot locate the explicit IP independently, and the server's run as docker container,so I have to config this to provide the service.

## How it could be?
Providing the "host name" as DNS might work.And it may also enhance the containers' service in the cloud environments.

Start by tracing how Seata currently configures the server IP and how that configuration is supplied in Docker containers. Check whether hostname-based DNS configuration is supported in the affected deployment path. Done means the service can use a host name instead of an explicit IP in the stated container and cloud environment, with the behavior verified.

Written by the indexing model from the issue text.