use braces for constructor

Author: rotu

rmw_cyclonedds_cpp/src/rmw_node.cpp

@@ -2221,7 +2221,7 @@ static void clean_waitset_caches()
      used ... */
   std::lock_guard<std::mutex> lock(gcdds.lock);
   for (auto && ws : gcdds.waitsets) {
-    std::unique_lock<std::mutex> lock2(ws->lock, std::try_to_lock);
+    std::unique_lock<std::mutex> lock2{ws->lock, std::try_to_lock};
     if (lock2.owns_lock()) {
       waitset_detach(ws);
     }