Running emqtt_bench triggers exception in KafkaCacheCursorFactory

[akrambek]

To Reproduce Steps to reproduce the behavior:

1. Checkout https://github.com/aklivity/zilla-examples/tree/main/mqtt.kafka.broker and start the stack
2. Download the correct emqx-bench binary: https://github.com/emqx/emqtt-bench/releases
3. ./bin/emqtt_bench pub -c 100 -I 10 -t bench/%i -s 256 --shortids

org.agrona.concurrent.AgentTerminationException: java.lang.NullPointerException: Cannot invoke "io.aklivity.zilla.runtime.binding.kafka.internal.types.KafkaEvaluation.ordinal()" because "evaluation" is null
	at io.aklivity.zilla.runtime.engine/io.aklivity.zilla.runtime.engine.internal.registry.EngineWorker.doWork(EngineWorker.java:707)
	at org.agrona.core/org.agrona.concurrent.AgentRunner.doDutyCycle(AgentRunner.java:291)
	at org.agrona.core/org.agrona.concurrent.AgentRunner.run(AgentRunner.java:164)
	at java.base/java.lang.Thread.run(Thread.java:1589)
Caused by: java.lang.NullPointerException: Cannot invoke "io.aklivity.zilla.runtime.binding.kafka.internal.types.KafkaEvaluation.ordinal()" because "evaluation" is null
	at io.aklivity.zilla.runtime.binding.kafka/io.aklivity.zilla.runtime.binding.kafka.internal.cache.KafkaCacheCursorFactory.asCondition(KafkaCacheCursorFactory.java:1097)
	at io.aklivity.zilla.runtime.binding.kafka/io.aklivity.zilla.runtime.binding.kafka.internal.stream.KafkaCacheClientFetchFactory.newStream(KafkaCacheClientFetchFactory.java:242)
	at io.aklivity.zilla.runtime.binding.kafka/io.aklivity.zilla.runtime.binding.kafka.internal.stream.KafkaCacheClientFactory.newStream(KafkaCacheClientFactory.java:141)
	at io.aklivity.zilla.runtime.engine/io.aklivity.zilla.runtime.engine.internal.registry.EngineWorker.handleBeginInitial(EngineWorker.java:1386)
	at io.aklivity.zilla.runtime.engine/io.aklivity.zilla.runtime.engine.internal.registry.EngineWorker.handleDefaultReadInitial(EngineWorker.java:1154)
	at io.aklivity.zilla.runtime.engine/io.aklivity.zilla.runtime.engine.internal.registry.EngineWorker.handleReadInitial(EngineWorker.java:1094)
	at io.aklivity.zilla.runtime.engine/io.aklivity.zilla.runtime.engine.internal.registry.EngineWorker.handleRead(EngineWorker.java:1041)
	at io.aklivity.zilla.runtime.engine/io.aklivity.zilla.runtime.engine.internal.concurent.ManyToOneRingBuffer.read(ManyToOneRingBuffer.java:181)
	at io.aklivity.zilla.runtime.engine/io.aklivity.zilla.runtime.engine.internal.registry.EngineWorker.doWork(EngineWorker.java:701)
	... 3 more
	Suppressed: java.lang.Exception: [engine/data#5]	[0x0505000000000ca7] streams=[consumeAt=0x002c2760 (0x0000000000ac2760), produceAt=0x002c2c60 (0x0000000000ac2c60)]
		at io.aklivity.zill