private static EmbeddedConnectCluster exactlyOnceSourceConnectCluster() {
        Map<String, String> workerProps = Collections.singletonMap(
                DistributedConfig.EXACTLY_ONCE_SOURCE_SUPPORT_CONFIG,
                "enabled"
        );
        return createOrReuseConnectWithWorkerProps(workerProps);
    }
Integration tests for Kafka Connect's connector offset management REST APIs
connect/runtime/src/test/java/org/apache/kafka/connect/integration/OffsetsApiIntegrationTest.java