message: fix a mistake in the comments of `FeatureConfig`.
diff: @@ -169,7 +169,7 @@ class FeatureConfig(
  `FeatureConfig`.
  Raises:
  - ValueError: if `max_sequence_length` non-negative.
  + ValueError: if `max_sequence_length` non-integer or negative.
  """
  if not isinstance(max_sequence_length, int) or max_sequence_length < 0:
  raise ValueError(
  