Use setThreadingModel to deploy worker verticle

Author: sbesson

src/main/java/com/glencoesoftware/omero/ms/pixelbuffer/PixelBufferMicroserviceVerticle.java

@@ -48,6 +48,7 @@
 import io.vertx.core.DeploymentOptions;
 import io.vertx.core.Handler;
 import io.vertx.core.Promise;
+import io.vertx.core.ThreadingModel;
 import io.vertx.core.buffer.Buffer;
 import io.vertx.core.eventbus.ReplyException;
 import io.vertx.core.http.HttpServer;
@@ -224,7 +225,7 @@ public void deploy(JsonObject config, Promise<Void> prom) {
                 ).orElse(DEFAULT_WORKER_POOL_SIZE);
         vertx.deployVerticle("omero:omero-ms-pixel-buffer-verticle",
                 new DeploymentOptions()
-                        .setWorker(true)
+                        .setThreadingModel(ThreadingModel.WORKER)
                         .setInstances(workerPoolSize)
                         .setWorkerPoolName("pixel-buffer-pool")
                         .setWorkerPoolSize(workerPoolSize)