fix(docs): incorrect prop name in custom edge Svelte example (#999)

Author: wiscaksono

sites/svelteflow.dev/src/content/learn/customization/custom-edges.mdx

@@ -121,7 +121,7 @@ to:
   const edges = useEdges();
 </script>
 
-<BaseEdge {id} {path} />
+<BaseEdge {id} path={edgePath} />
 <EdgeLabel x={labelX} y={labelY}>
   <button
     class="nodrag nopan"