Fix close call

Author: jasontedor

test/framework/src/test/java/org/elasticsearch/transport/nio/SimpleNioTransportTests.java

@@ -109,7 +109,7 @@ protected MockTransportService build(
     @Override
     protected void close(NioChannel nioChannel) {
         try {
-            nioChannel.getCloseFuture().awaitClose();
+            nioChannel.closeAsync().awaitClose();
         } catch (IOException e) {
             throw new UncheckedIOException(e);
         }