Errors excecuting a process do not show in UI with docker image.

**Describe the bug**
When I running the docker image of the flowable ui, error messages are not correctly displayed in the task app.

I am using the following command to start flowable-ui:

`docker run -p 8080:8080 flowable/flowable-ui`

I then create a simple process which I expect to raise a runtime exception, e.g. trying to send an email with no recipient.

When I start the process, I see the red error bar pop up but there is no text in the message. When I look a the 500 response from the server, I see that there is no message: property in the returned json.

**Expected behavior**
If instead I run the flowable-ui application in my IDE (I am using Intellij Idea with a spring boot application configuration), then the flowable-ui task application shows the correct error message when a runtime exception is raised.

If I inspect the 500 response from the server I can see that it contains a message: property and a trace: property in the returned json.

**Code**
This 500 response is from flowable running with docker:

`{"timestamp":"2022-07-26T10:30:02.002+00:00","status":500,"error":"Internal Server Error","path":"/flowable-ui/app/rest/task-forms/5eeceaec-0ccc-11ed-a089-0242ac110002"}`

This 500 response is from flowable running in my IDE:
`
{"timestamp":"2022-07-26T10:38:41.100+00:00","status":500,"error":"Internal Server Error","trace":"org.flowable.common.engine.api.FlowableException: No recipient could be found for sending email\n\tat ...java.base/java.lang.Thread.run(Thread.java:833)\n","message":"No recipient could be found for sending email","path":"/flowable-ui/app/rest/task-forms/34d0311d-09d0-11ed-809e-0242f7c1f792"}`

**Additional context**

I am running the docker image from the flowable repository and I am using the same jre version in my IDE. I imagine there is some configuration parameter preventing the trace and message from being returned but I can't find it and I believe the default behaviour should be to show this message to users running the docker image to test out flowable.

Inizia riproducendo l’errore tramite l’immagine Docker e confronta la risposta 500 da /flowable-ui/app/rest/task-forms/... con la risposta della configurazione Spring Boot IDE. Traccia il modo in cui la task app riceve e visualizza le eccezioni a runtime, quindi identifica la differenza di configurazione che rimuove i campi message e trace. Il lavoro è completato quando la task app basata su Docker visualizza il messaggio di errore a runtime.

Scritto dal modello di indicizzazione a partire dal testo della issue.