Automatically infer data type in input/output assignments

Imagine following assignment:

Where `processTrigger` is a process variable of a custom data type. When using this `processVariable` in assignment, fill in the Data Type automatically based on the process variable data type. It is a sensible default, user shouldn't be force to fill in the data type again.

*Acceptance criteria*
Whenever a user uses process_variable in Data Input/Output Assignments the Data Type of the process_variable is auto filled in dropdown.