message: refactor(api): Add success message to delete endpoint
diff: @@ -65,7 +65,7 @@ async def create_session(request):
  """
  session_type = request.match_info['type']
  if session_type not in ALLOWED_SESSIONS:
  - message = f'Session of type {session_type} is not supported'
  + message = f"Session of type {session_type} is not supported."
  return web.json_response(message, status=403)
  session_storage = request.app['com.opentrons.session_manager']
  @@ -96,9 +96,10 @@ async def delete_session(request):
  session_storage = request.app['com.opentrons.session_manager']
  current_session = session_storage.sessions.get(session_type)
  if not current_session:
  - response = {'message': f'A {session_type} session does not exist.'}
  + response = {"message": f"A {session_type} session does not exist."}
  return web.json_response(response, status=404)
  else:
  await current_session.hardware.home()
  del session_storage.sessions[session_type]
  - return web.json_response(status=200)
  + response = {'message': f"Successfully deleted {session_type} session."}
  + return web.json_response(response, status=200)
  