fix 2d sac

ml-agents/mlagents/trainers/tests/torch/test_simple_rl.py

         SAC_TORCH_CONFIG.hyperparameters, buffer_init_steps=2000
     )
     config = attr.evolve(
-        SAC_TORCH_CONFIG, hyperparameters=new_hyperparams, max_steps=10000
+        SAC_TORCH_CONFIG, hyperparameters=new_hyperparams, max_steps=6000
     )
     check_environment_trains(env, {BRAIN_NAME: config}, success_threshold=0.8)