Consumer should auto-commit prior to cooperative partition revocation

With the old "eager" reassignment logic, we always revoked all partitions prior to each rebalance. When auto-commit is enabled, a part of this process is committing current positions. Under the new "cooperative" logic, we defer revocation until after the rebalance, which means we can continue fetching while the rebalance is in progress. However, when reviewing KAFKA-14196, we noticed that there is no similar logic to commit offsets prior to this deferred revocation. This means that cooperative consumption is more likely to lead to have duplicate consumption even when there is no failure involved.