[Serverless Logic Web Tools] NoStackTraceException on the deployment if the workflow has a validation warning

[fantonangeli]

If there are errors in the WF you cannot deploy it, but if there are warnings like changing the start node to something wrong ie:
"start": "NotExistingNode",

It's possible to deploy the WF and it breaks the deployment showing the following error in the deployment page:
io.vertx.core.impl.NoStackTraceException

Steps to reproduce:

• Import the example in this issue or change the start node in the Greeting example
• Deploy on devmode on OpenShift (normal deployments are also affected)
• Open the deployment

Full example:
greeting-with-warning.sw.json