Order errors by descending id

Usually it is the latest errors that are interesting for the user.

trytond/trytond/ir/error.py

@@ -88,6 +88,7 @@ class Error(Workflow, ModelView, ModelSQL):
                 table,
                 (table.state, Index.Equality(cardinality='low')),
                 where=table.state.in_(['open', 'processing'])))
+        cls._order = [('id', 'DESC')]
         cls._transitions |= {
             ('open', 'processing'),
             ('processing', 'solved'),