smallrye-mutiny-vertx-web-client on kogito 1.27.x is of version 2.25.0 [1] while the smallrye mutiny used by Quarkus 2.7 LTS is 2.21.0.

[1] https://github.com/kiegroup/kogito-runtimes/blob/666a8b0be24b8a4858066fe384467beb118489c4/kogito-build/kogito-dependencies-bom/pom.xml#L59
[2] https://github.com/quarkusio/quarkus/blob/2.7/bom/application/pom.xml#L57

The vertx-web-client is looking for a DelegatingHandler class which exists only since 2.24.0, thus failing tests with

java.lang.NoClassDefFoundError: io/smallrye/mutiny/vertx/DelegatingHandler

We need to align the client to Quarkus 2.7 LTS version, which is 2.21.0.