[KafkaIO] Remove duplicate offset in range check

[sjvanrossum]

The fetcher (or fetch collector in later versions) in Kafka's client library already checks if a fetched record batch starts at the consumer's current position before returning any records in response to polling and otherwise ignores the batch.
See https://github.com/apache/kafka/blob/2.4.1/clients/src/main/java/org/apache/kafka/clients/consumer/internals/Fetcher.java#L675 and https://github.com/apache/kafka/blob/2.4.1/clients/src/main/java/org/apache/kafka/clients/consumer/KafkaConsumer.java#L1605.

Stacked on top of #34165.

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[github-actions]

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[github-actions]

Reminder, please take a look at this pr: @m-trieu @damccorm @johnjcasey @fozzie15

[damccorm]

@johnjcasey @fozzie15 could you please take a look?

[sjvanrossum]

@johnjcasey @fozzie15 I've rebased this PR on master instead of #34165 since there's no dependency between the two PRs.

[chamikaramj]

assign to next reviewer