test: add retry for default kms system test (#198)

Author: Gurov Ilya

tests/system/test_system.py

@@ -1905,6 +1905,7 @@ def test_blob_w_explicit_kms_key_name(self):
  (listed,) = list(self.bucket.list_blobs())
  self.assertTrue(listed.kms_key_name.startswith(kms_key_name))
 
+ @RetryErrors(unittest.TestCase.failureException)
  def test_bucket_w_default_kms_key_name(self):
  BLOB_NAME = "default-kms-key-name"
  OVERRIDE_BLOB_NAME = "override-default-kms-key-name"