Support for throwing a BPMN Error from a decision task

Hello,

**Is your feature request related to a problem? Please describe.**

My needs are descibed by this forum topic : https://forum.flowable.org/t/thow-a-bpmnerror-from-a-decision-task/8563

**Describe the solution you'd like**

Two solutions are suggested by @yvoswillens :
* provide the options to specify if a BPMN Error (and with what code) or a Java exception should be thrown when there are no hits.
* or to provide the same exception mapping mechanism that is available on service tasks

**Describe alternatives you've considered**

For now, to handle my needs, I modified my decision table.
I added an output column with a list of error codes as output values.
And some matching rules to make sure at least a hit is reached.


Inizia dalla discussione del forum collegata e confronta il comportamento no-hit delle decision tasks con il meccanismo di exception-mapping già disponibile sulle service tasks. Determina quale dei due approcci proposti è previsto, quindi verifica che una decision task possa produrre il BPMN Error o la Java exception richiesti quando nessuna regola corrisponde.

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