Fixed #35643 -- Fixed a crash when ordering a QuerySet by a reference containing "__".

Regression in b0ad41198b.

Refs #34013. The initial logic did not consider that annotation aliases
can include lookup or transform separators.

Thanks Gert Van Gool for the report and Mariusz Felisiak for the review.

tests/aggregation/tests.py

@@ -1750,6 +1750,26 @@ class AggregateTestCase(TestCase):
             ],
         )
 
+    def test_order_by_aggregate_default_alias(self):
+        publisher_books = (
+            Publisher.objects.values("book")
+            .annotate(Count("book"))
+            .order_by("book__count", "book__id")
+            .values_list("book", flat=True)
+        )
+        self.assertQuerySetEqual(
+            publisher_books,
+            [
+                None,
+                self.b1.id,
+                self.b2.id,
+                self.b3.id,
+                self.b4.id,
+                self.b5.id,
+                self.b6.id,
+            ],
+        )
+
     def test_empty_result_optimization(self):
         with self.assertNumQueries(0):
             self.assertEqual(