message: Fix a typo suggested in cl/372620995
diff: @@ -488,7 +488,7 @@ class Layer(module.Module, version_utils.LayerVersionSelector):
  inputs: Input tensor, or dict/list/tuple of input tensors.
  The first positional `inputs` argument is subject to special rules:
  - `inputs` must be explicitly passed. A layer cannot have zero
  - arguments, and inputs cannot have been provided via the default value
  + arguments, and `inputs` cannot be provided via the default value
  of a keyword argument.
  - NumPy array or Python scalar values in `inputs` get cast as tensors.
  - Keras mask metadata is only collected from `inputs`.
  