Complemented pickle test for ValuesQuerySet with related field

Refs #14515.

tests/queryset_pickle/models.py

@@ -46,6 +46,7 @@ class Group(models.Model):
 
 
 class Event(models.Model):
+    title = models.CharField(max_length=100)
     group = models.ForeignKey(Group)
 
 

tests/queryset_pickle/tests.py

@@ -100,6 +100,11 @@ class PickleabilityTestCase(TestCase):
         self.assert_pickles(Happening.objects.values('name'))
         self.assert_pickles(Happening.objects.values('name').dates('when', 'year'))
 
+        # ValuesQuerySet with related field (#14515)
+        self.assert_pickles(
+            Event.objects.select_related('group').order_by('title').values_list('title', 'group__name')
+        )
+
     def test_pickle_prefetch_related_idempotence(self):
         g = Group.objects.create(name='foo')
         groups = Group.objects.prefetch_related('event_set')