remove uneccesary type from set_actions

ml-agents-envs/mlagents_envs/base_env.py

     NamedTuple,
     Tuple,
     Optional,
-    Union,
     Dict,
     Iterator,
     Any,
         """
 
     @abstractmethod
-    def set_actions(
-        self, behavior_name: BehaviorName, action: Union[np.ndarray]
-    ) -> None:
+    def set_actions(self, behavior_name: BehaviorName, action: np.ndarray) -> None:
         """
         Sets the action for all of the agents in the simulation for the next
         step. The Actions must be in the same order as the order received in
 
     @abstractmethod
     def set_action_for_agent(
-        self, behavior_name: BehaviorName, agent_id: AgentId, action: Union[np.ndarray]
+        self, behavior_name: BehaviorName, agent_id: AgentId, action: np.ndarray
     ) -> None:
         """
         Sets the action for one of the agents in the simulation for the next