Fix assertEqual parameter order (expected, actual)

This ensures the failure message, if any, is reflective of the
intended value.

tests.py

@@ -131,7 +131,7 @@ class SnapPassRoutesTestCase(TestCase):
 
         for ua in a_few_sneaky_bots:
             rv = self.app.get('/{0}'.format(key), headers={ 'User-Agent': ua })
-            self.assertEqual(rv.status_code, 404)
+            self.assertEqual(404, rv.status_code)
 
 
 if __name__ == '__main__':