no __aiter__ method in FakeAIOKafkaConsumer

[paul-callahan]

The pattern to use with fetching msgs from aiokafka's AIOKafkaConsumer appears to be:

            consumer = aiokafka.AIOKafkaConsumer(...)
            async for message in consumer:
                self.logger.info(f"Received message: {message}")

But using FakeAIOKafkaConsumer in place of doesn't work because of the lack of aiter method.

[PeterJCLaw]

Just checking you've seen that this is already reported at #224?