[JAVA](native-client) Add support for UnaryInterceptors

[dschodits-secunet]

This Pr solves Issue: #22333 by adding Support for UnaryInterceptors in the Java-Native-Client

This is done by adding a new config option called "useUnaryInterceptor" which changes the Datatype of the ResponseInterceptor from a Consumer to a UnaryInterceptor. With a variable reassignment this allows for changing an incomming response before it gets passed.

This change doesn't break any existing Systems due to the default value of false for the "useUnaryInterceptor".

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  @bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10) @martin-mfg (2023/08)

[wing328]

suggestion:

{{#useUnaryInterceptor}}import 
java.util.function.UnaryOperator;
{{/useUnaryInterceptor}}

to avoid blank lines

[wing328]

what about showing this comment only when the option is enabled?