LibWeb: Stub out two functions on SVGGeometryElement

These two were called by Discord while loading:

- float getTotalLength();
- DOMPoint getPointAtLength(float distance);

Userland/Libraries/LibWeb/SVG/SVGGeometryElement.h

@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibWeb/Geometry/DOMPoint.h>
 #include <LibWeb/SVG/SVGGraphicsElement.h>
 
 namespace Web::SVG {
@@ -19,6 +20,9 @@ public:
 
     virtual Gfx::Path& get_path() = 0;
 
+    float get_total_length();
+    NonnullRefPtr<Geometry::DOMPoint> get_point_at_length(float distance);
+
 protected:
     SVGGeometryElement(DOM::Document& document, DOM::QualifiedName qualified_name);
 };