fix: declare assignor variable for examples & clean up log format (#2… #118

Job	Run time
Test with Kafka 1.0.2 / Test with Kafka 1.0.2	6m 19s
Test with Kafka 2.0.1 / Test with Kafka 2.0.1	7m 3s
Test with Kafka 2.2.2 / Test with Kafka 2.2.2	6m 44s
Test with Kafka 2.6.2 / Test with Kafka 2.6.2	7m 16s
Test with Kafka 2.8.2 / Test with Kafka 2.8.2	7m 24s
Test with Kafka 3.0.2 / Test with Kafka 3.0.2	7m 31s
Test with Kafka 3.3.2 / Test with Kafka 3.3.2	7m 24s
Test with Kafka 3.6.0 / Test with Kafka 3.6.0	7m 19s
	57m 0s

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