Migrate Keycloak version to 15.1.1

[acasanova99]

It is important to think in the new versions of KC, lest start by the 15.1.1 Once we use a KC CLI instead the realm file we should go for the lastest version available

[acasanova99]

When migrating:

... (vert.x-eventloop-thread-9) Error while creating User: The arguments provided to the function are not compatible with the keycloak's standard
The user representation provided to Keycloak is incorrect

TODO: keep original exception