Add unbuffered to rebuilder supervisor configuration

There was an issue where stdout wasn't making it to the logs, and this
fixed it.

base/torque/ansible/roles/torque/templates/supervisor-torque-rebuilder.conf.j2

 [program:{{ supervisor_torque_name }}-rebuilder]
 directory={{ torque_install_directory }}
 user:{{ deployment_user }}
-command=pipenv run python manage.py run_cache_rebuilder
+command=pipenv run python -u manage.py run_cache_rebuilder
 autostart=true
 autorestart=true
 redirect_stderr=true