@Override
    protected Set<WorkerHandle> workers() {
        return connectWorker != null
                ? Collections.singleton(connectWorker)
                : Collections.emptySet();
    }
Start a standalone embedded connect worker. Internally, this class will spin up a Kafka cluster,
set up any tmp directories. and clean them up on exit. Methods on the same
{@code EmbeddedConnectStandalone} are not guaranteed to be thread-safe.
connect/runtime/src/test/java/org/apache/kafka/connect/util/clusters/EmbeddedConnectStandalone.java