Have a service that retrieves the parties with a particular roleTypeId

Various create or edit forms involving assigning parties to a role for a particular artefact (or object, like agreement, order, quote, invoice, etc) allow to select from all parties and from all roles.

See as an example of this: https://demo-trunk.ofbiz.apache.org/ordermgr/control/EditQuoteRole?quoteId=CQ0001

However, for many of those artefacts (or objects) there are specific roleType records defined to cater to either permission related functions or to provide flow functions regarding the objects.

In order to help assigning a party for a given role associated to the object, a generic service is required that retrieves the parties associated with the role.