test_util: tolerate unordered repr of NumDict

NumDict does not make any claims about the order of its repr(), so the
test needs to be prepared for it to be stringified in any order. On unix
the old test happened to pass, but on certain windows boxes (maybe
certain versions of python?), it failed. Fixes ticket:2736.

src/allmydata/test/test_util.py

@@ -1353,7 +1353,8 @@ class DictUtil(unittest.TestCase):
         self.failUnlessEqual(d.item_with_largest_value(), ("b", 6))
 
         d = dictutil.NumDict({"a": 1, "b": 2})
-        self.failUnlessEqual(repr(d), "{'a': 1, 'b': 2}")
+        self.failUnlessIn(repr(d), ("{'a': 1, 'b': 2}",
+                                    "{'b': 2, 'a': 1}"))
         self.failUnless("a" in d)
 
         d2 = dictutil.NumDict({"c": 3, "d": 4})