fix(test): Set SENTRY_ENABLE_QUEUE_TRACING for Kafka system tests

When SENTRY_AUTO_INIT=true with the OTel agent, Sentry is initialized
early by SentryAutoConfigurationCustomizerProvider before Spring Boot
loads application-kafka.properties. Without the env var, queue tracing
stays disabled and OTel messaging spans are not mapped to
queue.publish/queue.process ops, causing
KafkaOtelCoexistenceSystemTest to fail.

Co-Authored-By: Claude <noreply@anthropic.com>

Author: adinauer

test/system-test-runner.py

@@ -442,6 +442,7 @@ def start_spring_server(self, sample_module: str, java_agent: str, java_agent_au
 
         if self.module_requires_kafka_profile(sample_module):
             env["SPRING_PROFILES_ACTIVE"] = "kafka"
+            env["SENTRY_ENABLE_QUEUE_TRACING"] = "true"
             print("Enabling Spring profile: kafka")
         else:
             env.pop("SPRING_PROFILES_ACTIVE", None)