[Java][Flight] How can a FlightClient connect to multiple servers?

### Describe the usage question you have. Please include as many useful details as possible.

Our backend service is a cluster that allows clients to connect to any service. How does a FlightClient connect to multiple servers and maintain the authentication status. Our goal is load balancing. The server uses FlightService and grpc Server, but the authentication is in FlightService. I don't know how to maintain the authentication status of multiple servers in one FlightClient.

### Component(s)

Java

A issue menciona FlightClient, FlightService e o gRPC Server; comece rastreando como o cliente Java gerencia as conexões e como a autenticação é estabelecida no FlightService. Determine se é possível usar vários servidores mantendo a autenticação para balanceamento de carga; considera-se concluído quando houver uma resposta concreta e documentada ou um follow-up claramente delimitado.

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