Handle an ClientHello message. Send available containers to the client

async def handle_client_hello(self, client_addr, _: ClientHello):
        """ Handle an ClientHello message. Send available containers to the client """
        self._logger.info("New client connected %s", client_addr)
        self._registered_clients.add(client_addr)
        await self.send_container_update_to_client([client_addr])