bpo-30445: Allow appended output in RecursionError message

Running under coverage sometimes causes 'in comparison' to be added to the end of the RecursionError message, which is acceptable.

Patched by Maria Mckinley
diff --git a/Lib/test/test_traceback.py b/Lib/test/test_traceback.py
index 7276bc7..e483353 100644
--- a/Lib/test/test_traceback.py
+++ b/Lib/test/test_traceback.py
@@ -344,7 +344,8 @@
         # 2nd last line contains the repetition count
         self.assertEqual(actual[:-2], expected[:-2])
         self.assertRegex(actual[-2], expected[-2])
-        self.assertEqual(actual[-1], expected[-1])
+        # last line can have additional text appended
+        self.assertIn(expected[-1], actual[-1])
 
         # Check the recursion count is roughly as expected
         rec_limit = sys.getrecursionlimit()