Kafka Cooperative Sticky Assignor results in significant duplicate consumption

Details may be found within the linked document:

[Kafka Cooperative Sticky Assignor Issue : Duplicate Consumption | https://docs.google.com/document/d/1E7qAwGOpF8jo_YhF4NwUx9CXxUGJmT8OhHEqIg7-GfI/edit?usp=sharing]

In a nutshell, we noticed that the Cooperative Sticky Assignor resulted in significant duplicate message consumption. During last year's F1 Grand Prix events and World Cup soccer events, our company's Kafka-based platform received live-traffic. This live traffic, coupled with autoscaled consumers resulted in as much as 70% duplicate message consumption at the Kafka consumers. 

In December 2022, we ran a synthetic load test to confirm that duplicate message consumption occurs during consumer scale out/in and Kafka partition rebalancing when using the Cooperative Sticky Assignor. This issue does not occur when using the Range Assignor.