LibWeb: Remove declarations for non-existent methods

Author: https://github.com/AtkinsSJ
Commit: 7891ad2a28
Pull-request: https://github.com/SerenityOS/serenity/pull/17203
Reviewed-by: https://github.com/linusg ✅

Userland/Libraries/LibWeb/HTML/HTMLImageElement.h

@@ -51,8 +51,6 @@ private:
     virtual void initialize(JS::Realm&) override;
     virtual void apply_presentational_hints(CSS::StyleProperties&) const override;
 
-    void animate();
-
     virtual JS::GCPtr<Layout::Node> create_layout_node(NonnullRefPtr<CSS::StyleProperties>) override;
 
     ImageLoader m_image_loader;