Updated keycloak to 19.0.0

[vidhya03]

fix https://github.com/jhipster/generator-jhipster/issues/19247

Upgrade keycloak to 19.0.0

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[CLAassistant]

All committers have signed the CLA.

[DanielFran]

@vidhya03 Can you sign the CLA?

[vidhya03]

@vishal423 Could you please suggest how to run the tests locally. I am new to this. thanks a lot

[mraible]

Is there anything I can do to help move this along?

[DanielFran]

Superseded by https://github.com/jhipster/generator-jhipster/pull/19540