post_complete_message_to_sweep_process in main_fedavg.py is useless.

In experiments/distributed/moleculenet/main_fedavg.py, several lines of codes at the end of the file are shown as follows:

```
if process_id == 0:
post_complete_message_to_sweep_process(args)

```
Actually, these two lines of codes cannot be run, since before getting into them the application will call MPI_Abort to terminate the processes.