Update two tests following review comments.

Author: marcharper

axelrod/tests/unit/test_match.py

@@ -359,8 +359,8 @@ def test_sample_length(self):
             (2, 0.6, 1),
             (3, 0.4, 2),
         ]:
-            rg = RandomGenerator(seed)
-            r = rg.random()
+            rng = RandomGenerator(seed)
+            r = rng.random()
             self.assertEqual(axl.match.sample_length(prob_end, r), expected_length)
 
     def test_sample_with_0_prob(self):

axelrod/tests/unit/test_tournament.py

@@ -757,9 +757,10 @@ def test_seeding_equality(self, seed):
             repetitions=100,
             seed=seed
         )
-        results1 = tournament1.play(processes=2)
-        results2 = tournament2.play(processes=2)
-        self.assertEqual(results1.ranked_names, results2.ranked_names)
+        for _ in range(4):
+            results1 = tournament1.play(processes=2)
+            results2 = tournament2.play(processes=2)
+            self.assertEqual(results1.ranked_names, results2.ranked_names)
 
     def test_seeding_inequality(self):
         players = [axl.Random(0.4), axl.Random(0.6)]