self.reward_range is wrong in the file rlenv/StockTradingEnv0.py

[GuoxiangZu]

https://github.com/wangshub/RL-Stock/blob/22d2cbf88f627750562c27462817f9bb9f492cee/rlenv/StockTradingEnv0.py#L28 " self.reward_range = (0, MAX_ACCOUNT_BALANCE) " is wrong, as https://github.com/wangshub/RL-Stock/blob/22d2cbf88f627750562c27462817f9bb9f492cee/rlenv/StockTradingEnv0.py#L113 "reward = 1 if reward > 0 else -100" which means reward could be -100 with is below 0.