Small html cleanup

src/web/html/HtmlDocument.h

@@ -1,15 +1,17 @@
 #pragma once
-#include <memory>
+
 #include "XmlDocument.h"
 
+#include <memory>
+
 class HtmlDocument : public XmlDocument
 {
 public:
-
     HtmlDocument();
 
-    static std::shared_ptr<HtmlDocument> Create();
+    virtual ~HtmlDocument() = default;
 
+    static std::unique_ptr<HtmlDocument> Create();
 };
 
-using HtmlDocumentPtr = std::shared_ptr<HtmlDocument>;
+using HtmlDocumentPtr = std::unique_ptr<HtmlDocument>;