Workflows; Workflow Item properties no longer mandatory so they can be set by Script code

The following properties in the Workflow Item wizard are no longer mandatory so that the Workflow Type Script can determine them at runtime without having to set them to arbitrary values in the wizard:

• Decision Card

NOTE: This behaviour was already available by clicking the 'Finish' button on the wizard from the first page without specifying a Decision Card. This change just makes that process more intuitive.