Is your feature request related to a problem?
If we use consumer.consume(num_messages=100) src for receiving messages, ConfluentKafkaInstrumentor doesn't send spans for this.
Describe the solution you'd like
ConfluentKafkaInstrumentor should wrap consume method the same as the poll method.
Additional context
We could add messaging.batch.message_count to semconv and use it in a span tag. Relates to batch-receiving in opentelemetry-semantic-conventions.