Add Unity command line arguments

ml-agents-envs/mlagents/envs/environment.py

         docker_training: bool = False,
         no_graphics: bool = False,
         timeout_wait: int = 30,
+        args: list = [],
     ):
         """
         Starts a new unity environment and establishes a connection with the environment.
         :bool no_graphics: Whether to run the Unity simulator in no-graphics mode
         :int timeout_wait: Time (in seconds) to wait for connection from environment.
         :bool train_mode: Whether to run in training mode, speeding up the simulation, by default.
+        :list args: Addition Unity command line arguments
         """
 
         atexit.register(self._close)
                 "the worker-id must be 0 in order to connect with the Editor."
             )
         if file_name is not None:
-            self.executable_launcher(file_name, docker_training, no_graphics)
+            self.executable_launcher(file_name, docker_training, no_graphics, args)
         else:
             logger.info(
                 "Start training by pressing the Play button in the Unity Editor."
     def reset_parameters(self):
         return self._resetParameters
 
-    def executable_launcher(self, file_name, docker_training, no_graphics):
+    def executable_launcher(self, file_name, docker_training, no_graphics, args):
         cwd = os.getcwd()
         file_name = (
             file_name.strip()
                             "-batchmode",
                             "--port",
                             str(self.port),
-                        ]
+                        ] + args
-                        [launch_string, "--port", str(self.port)]
+                        [launch_string, "--port", str(self.port)] + args
                     )
             else:
                 """