[Fix #3460] Fix ClassCastException on Exception mapping

[fjtirado]

Fixes #3460

[kie-ci3]

PR job #3 was: UNSTABLE
Possible explanation: This should be test failures

Reproducer

build-chain build full_downstream -f 'https://raw.githubusercontent.com/${AUTHOR:apache}/incubator-kie-kogito-pipelines/${BRANCH:main}/.ci/buildchain-config-pr-cdb.yaml' -o 'bc' -p apache/incubator-kie-kogito-runtimes -u #3461 --skipParallelCheckout

NOTE: To install the build-chain tool, please refer to https://github.com/kiegroup/github-action-build-chain#local-execution

Please look here: https://ci-builds.apache.org/job/KIE/job/kogito/job/main/job/pullrequest_jobs/job/kogito-runtimes-pr/job/PR-3461/3/display/redirect

Test results:

• PASSED: 3253
• FAILED: 2

Those are the test failures:

org.kie.kogito.quarkus.workflows.ExpressionRestIT.testExpressionOutputValidation

1 expectation failed.
JSON path id doesn't match.
Expected: not null
Actual: null

org.kie.kogito.quarkus.workflows.RetriggerIT.testRetrigger

Unnamed path parameter cannot be null (path parameter at index 0 is null)

[kie-ci3]

PR job #4 was: UNSTABLE
Possible explanation: This should be test failures

Reproducer

build-chain build full_downstream -f 'https://raw.githubusercontent.com/${AUTHOR:apache}/incubator-kie-kogito-pipelines/${BRANCH:main}/.ci/buildchain-config-pr-cdb.yaml' -o 'bc' -p apache/incubator-kie-kogito-runtimes -u #3461 --skipParallelCheckout

NOTE: To install the build-chain tool, please refer to https://github.com/kiegroup/github-action-build-chain#local-execution

Please look here: https://ci-builds.apache.org/job/KIE/job/kogito/job/main/job/pullrequest_jobs/job/kogito-runtimes-pr/job/PR-3461/4/display/redirect

Test results:

• PASSED: 3254
• FAILED: 1

Those are the test failures:

org.kie.kogito.addons.quarkus.knative.serving.customfunctions.it.KnativeServingAddonIT.execute404

1 expectation failed.
Expected status code <500> but was <404>.

[gmunozfe]

Looks good to me, great solution @fjtirado !