[Bug]: ReadFromKafka not forwarding in streaming mode version on portable runners

### What happened?

ReadFromKafka not forwarding in streaming mode.
using apache-beam 2.44.0

beam_options = PipelineOptions(streaming = True)
pipeline = beam.Pipeline(options=beam_options)

messages = (
pipeline
| 'Read from Kafka' >> ReadFromKafka(
consumer_config=json.load(open("config/consumer_config_beam.json")),
topics=topic
)
| 'Print messages' >> beam.Map(lambda message: print("received!"))
)

Hello, in the code above, the code is stuck on ReadFromKafka.
Adding max_num_records will only wait for the specific amount of data and them forward them to the next step and ends the codes.
(I am using the DirectRunner I need to run the code locally)

### Issue Priority

Priority: 1 (data loss / total loss of function)

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