Remove callable functions parameter from kafka operator template_fields

[gopidesupavan]

closes: #42502

The Kafka ConsumeFromTopicOperator and ProduceToTopicOperator are failing to resolve callable template fields. For a callable to work with template functions, it must accept both the context and jinja_env.

If we include producer_function and apply_function in the template fields, all current users will need to modify their scripts to accept both context and jinja_env. and some minor updates require in kafka operator.

I also tested another scenario where the function does accept context and jinja_env, but in the UI template field, it appears as a generated type object(please check below screenshot). Since there isn’t much value in displaying this field as a generated type object, I believe it's better to remove these from the template fields altogether.

Any other suggestion please?

Removed the fields and executed kafka system test.

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[shahar1]

I'm not entirely sure that removing these parameters is the right way to deal with it (then you'll break compatibility with older Airflow versions where it works).
@uranusjr / @raphaelauv - I would be happy for your feedback.

[raphaelauv]

Yes I did the same for #39948

That was the only callable that was in the templated_fields of the operator that I detected thanks to a unit test breaking

[gopidesupavan]

I'm not entirely sure that removing these parameters is the right way to deal with it (then you'll break compatibility with older Airflow versions where it works). @uranusjr / @raphaelauv - I would be happy for your feedback.

Thanks for the review. Yes i completely agree. but IMHO keeping these parameters also cause problems here. https://github.com/apache/airflow/blob/main/airflow/models/abstractoperator.py#L768

here the callable value args has only context and jinja_env, if the function does accepts more arguments this would fail ?.

Happy for any other suggestions :)