[FlightRPC][Java] Provide standard way to get client IP address

Obtaining the IP address of the client can be [accomplished via gRPC](https://github.com/apache/arrow-cookbook/issues/196), but the gRPC interface exposing this information is considered unstable.  It would be good to expose this through a standard interface in Flight, both to buffer any future changes/instability in gRPC, but also in support of alternative transports.

**Reporter**: [Todd Farmer](https://issues.apache.org/jira/browse/ARROW-16565) / @toddfarmer

_{**Note**: *This issue was originally created as [ARROW-16565](https://issues.apache.org/jira/browse/ARROW-16565). Please see the [migration documentation](https://github.com/apache/arrow/issues/14542) for further details.*}