[Java][FlightRPC] Update benchmark to be on par with C++

See https://github.com/apache/arrow/issues/13980

The Java benchmark isn't comparable out of the box (and it seems like there's an unexplained gap between it and the C++ benchmark)

**Reporter**: [David Li](https://issues.apache.org/jira/browse/ARROW-17537) / @lidavidm

_{**Note**: *This issue was originally created as [ARROW-17537](https://issues.apache.org/jira/browse/ARROW-17537). Please see the [migration documentation](https://github.com/apache/arrow/issues/14542) for further details.*}

Comece lendo a issue 13980 do Apache Arrow vinculada e compare o benchmark de Java FlightRPC com seu equivalente em C++. Identifique por que os benchmarks não são comparáveis e o que causa a diferença de desempenho relatada. O trabalho estará concluído quando o benchmark de Java estiver alinhado com o benchmark de C++ e produzir resultados comparáveis.

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