[Java][microprofile] enumUnknownDefaultCase true now returns correctly

[skstrifork]

Fix #19674

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[wing328]

cc
@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]

thanks for the PR. let's give it a try