Small MessageProcessor fix

Author: sam

source/ev3dev2/simulator/connection/MessageProcessor.py

@@ -113,7 +113,8 @@ def _process_stop_command_values(self, command: StopCommand, side: str) -> Tuple
         """
 
         if side == 'center':
-            return self.command_processor.process_stop_command_degrees(command)
+            dpf, frames, run_time = self.command_processor.process_stop_command_degrees(command)
+            return -dpf, frames, run_time
         else:
             return self.command_processor.process_stop_command_pixels(command)