[2.0.x] Refs #28958 -- Added a test for ModelAdmin with query expressions in ordering.

This provides additional test coverage but isn't a regression test for
the ticket's issue.

Backport of 1d00923848 from master

tests/admin_ordering/tests.py

@@ -1,6 +1,7 @@
 from django.contrib import admin
 from django.contrib.admin.options import ModelAdmin
 from django.contrib.auth.models import User
+from django.db.models import F
 from django.test import RequestFactory, TestCase
 
 from .models import (
@@ -62,6 +63,13 @@ class TestAdminOrdering(TestCase):
         names = [b.name for b in ma.get_queryset(request)]
         self.assertEqual(['Radiohead', 'Van Halen', 'Aerosmith'], names)
 
+    def test_specified_ordering_by_f_expression(self):
+        class BandAdmin(ModelAdmin):
+            ordering = (F('rank').desc(nulls_last=True),)
+        band_admin = BandAdmin(Band, site)
+        names = [b.name for b in band_admin.get_queryset(request)]
+        self.assertEqual(['Aerosmith', 'Van Halen', 'Radiohead'], names)
+
     def test_dynamic_ordering(self):
         """
         Let's use a custom ModelAdmin that changes the ordering dynamically.