docstr: Bin reward to {+1, 0, -1} by its sign.
code: def reward(self, reward):
      """Bin reward to {+1, 0, -1} by its sign."""
      return np.sign(reward)
  
imports: from collections import deque
  import gymnasium
  from gymnasium import spaces
  import numpy
  from typing import Union
  from ray.rllib.utils.annotations import PublicAPI
  from ray.rllib.utils.images import rgb2gray, resize
label_desc: Use image node_id 2 for calling the ClipRewardEnv obj's underlying member method code with example usage: obj.reward(reward) and returns: np