Fix default ordering for build orders (#3626)

- Order by reference
- Show "newer" references first

InvenTree/build/api.py

@@ -100,6 +100,8 @@ class BuildList(APIDownloadMixin, ListCreateAPI):
         'reference': ['reference_int', 'reference'],
     }
 
+    ordering = '-reference'
+
     search_fields = [
         'reference',
         'title',