Send a message to the stdin of a container, with the right data
        :param write_stream: asyncio write stream to the stdin of the container
        :param message: dict to be msgpacked and sent

async def _write_to_container_stdin(self, write_stream, message):
        """
        Send a message to the stdin of a container, with the right data
        :param write_stream: asyncio write stream to the stdin of the container
        :param message: dict to be msgpacked and sent
        """
        msg = msgpack.dumps(message, encoding="utf8", use_bin_type=True)
        self._logger.debug("Sending %i bytes to container", len(msg))
        write_stream.write(struct.pack('I', len(msg)))
        write_stream.write(msg)
        await write_stream.drain()