Assignments not displaying correctly in Deals / Leads list view when # of assignees > 1

[joshuarestivo]

CRM: develop branch
Frappe: 15.42.0

If a Deal or Lead is assigned to more than one user, the Assignment is reflected correctly within the document view. However, the corresponding list views only show a single assignee. This is confusing for the user and all assignments should be visible in list views.