[java] Close the underlying websocket for JDK 11 Http Client

Author: pujagani

java/src/org/openqa/selenium/remote/http/jdk/JdkHttpClient.java

@@ -306,9 +306,9 @@ public HttpResponse execute(HttpRequest req) throws UncheckedIOException {
   @Override
   public void close() {
     executorService.shutdownNow();
-//    if (this.websocket != null) {
-//      this.websocket.close();
-//    }
+    if (this.websocket != null) {
+      this.websocket.close();
+    }
     this.client = null;
   }