Suggestion: AgentXXX.py if_act_target if_cri_target

[Yonv1943]

There are bug in if_act_target and if_cri_target in AgentBase.py

class AgentXXX.__init__() should set args.if_cri_target = getattr(self, "if_cri_target", True) (or False) in default.

Takes AgentDQN as an example, the following code should be changed.

https://github.com/AI4Finance-Foundation/ElegantRL/blob/3ded1cef5d9c9100422935141b07d3ec5301db4b/elegantrl/agents/AgentDQN.py#L21-L26

Change to fhe following code (as ElegantRL HelloWorld version do): https://github.com/AI4Finance-Foundation/ElegantRL/blob/3ded1cef5d9c9100422935141b07d3ec5301db4b/elegantrl_helloworld/agent.py#L62-L69

[zhumingpassional]

1 If the default value is true, how to set it as false?

2 if getattr is to set value for an attr, it should be setattr. getattr only gets values instead of changing values.

[uzhao]

Isn't it self.if_act_target?