Add a new condition value field for multiple-choice selection.
Review Request #12330 — Created June 2, 2022 and submitted
We have existing code that makes it easy to add multiple-choice
selections for models based on a queryset, but we didn't have anything
for multiple-choice selections based on just a set of choices. This
change adds a value field to do that.
Used this in Review Board. Saw that existing values were loaded properly
and new values were saved correctly.