message: Remove the hidden experimental attribute from the public document
diff: @@ -199,13 +199,6 @@ class TargetSpec(object):
  that may not be linked in by default with the TF ops that are provided
  when using the SELECT_TF_OPS path. The client is responsible for linking
  these ops into the target runtime.
  - _experimental_custom_op_registerers: Experimental flag, subject to change.
  - List of str (symbol names) or functions that take a pointer to a
  - MutableOpResolver and register TensorFlow Lite custom ops. When passing
  - functions, use a pybind function that takes a uintptr_t that can be recast
  - as a pointer to a MutableOpResolver. The TensorFlow Lite custom ops in the
  - registerers will be used when the representative data is given and the
  - post training quantization is enabled at the same time.
  """
  def __init__(self,
  