Description of the problem:
When the execution of a workflow fails from the UI, a confusing message is shown

How reproducible:
100%

Steps to reproduce:

1. Install a workflow, ie. MTA v7

2. In the configmap set quarkus.rest-client.mta_json.url = ${mta.url}/hub (this will cause an error at the 1st state)

3. Set the error message

Actual results:

Expected results:

The error returned by the workflow should be shown and no request should be done to the DI GraphQL endpoint if the instance ID is not there