Perform full intended assertion in test

Since Python 2.3 sorted() has been guaranteed to be stable. The comment
was wrong, and thus it makes sense to do the full assertion as clearly
intended.

Signed-off-by: Rodrigo Tobar <rtobar@icrar.org>

Author: rtobar

tests/messages/test_normalized_string.py

@@ -14,4 +14,4 @@ def test_normalized_string():
     assert ab1 <= ab2  # __le__
     assert ab1 != ac1  # __ne__
     assert not z  # __nonzero__ / __bool__
-    assert sorted([ab1, ab2, ac1])  # the sort order is not stable so we can't really check it, just that we can sort
+    assert sorted([ab1, ab2, ac1]) == [ab1, ab2, ac1] # sorted() is stable