This function returns the user name of the last user who had the current issue assigned, and currently plays a project role with name projectRoleName in current issue's project, or ""
if the current issue was never assigned to a user currently in the project role.
lastAssigneeInRole(string projectRoleName) #Output: Text
Variant where you can additionally define issueKey.
lastAssigneeInRole(string projectRoleName, string issueKey) #Output: Text