fix ci & test

Author: wl2027

smoke-tests-otel-starter/spring-boot-common/src/main/java/io/opentelemetry/spring/smoketest/AbstractJvmKafkaSpringStarterSmokeTest.java

@@ -61,8 +61,6 @@ void setUpContext() {
                 "spring.kafka.consumer.linger-ms=10",
                 "spring.kafka.listener.idle-between-polls=1000",
                 "spring.kafka.producer.transaction-id-prefix=test-");
-    System.setProperty(
-        "otel.instrumentation.kafka.experimental-span-attributes", String.valueOf(true));
   }
 
   @SuppressWarnings("unchecked")

smoke-tests-otel-starter/spring-boot-common/src/main/java/io/opentelemetry/spring/smoketest/AbstractKafkaSpringStarterSmokeTest.java

@@ -39,16 +39,11 @@ abstract class AbstractKafkaSpringStarterSmokeTest extends AbstractSpringStarter
   protected static AttributeAssertion bootstrapServersAssertion() {
     return satisfies(
         MESSAGING_KAFKA_BOOTSTRAP_SERVERS,
-        listAssert -> {
-          if (Boolean.getBoolean("otel.instrumentation.kafka.experimental-span-attributes")) {
+        listAssert ->
             listAssert
                 .isNotEmpty()
                 .allSatisfy(
-                    server -> org.assertj.core.api.Assertions.assertThat(server).isNotEmpty());
-          } else {
-            listAssert.isNullOrEmpty();
-          }
-        });
+                    server -> org.assertj.core.api.Assertions.assertThat(server).isNotEmpty()));
   }
 
   @SuppressWarnings("deprecation") // using deprecated semconv