Remove version annotation attribute in perf tool

Not necessary.

Author: acogoluegnes

src/main/java/com/rabbitmq/stream/perf/StreamPerfTest.java

@@ -84,7 +84,6 @@
     name = "stream-perf-test",
     mixinStandardHelpOptions = false,
     showDefaultValues = true,
-    version = "perftest 0.1",
     description = "Tests the performance of stream queues in RabbitMQ.")
 public class StreamPerfTest implements Callable<Integer> {