fix: fix nav item ts, asked by shijia

packages/semi-ui/navigation/index.tsx

@@ -267,7 +267,7 @@ class Nav extends BaseComponent<NavProps, NavState> {
                     if (Array.isArray(item.items) && item.items.length) {
                         return (
                             <SubNav key={item.itemKey || String(level) + idx} {...item as SubNavPropsWithItems} level={level}>
-                                {this.renderItems(item.items, level + 1)}
+                                {this.renderItems(item.items as (SubNavPropsWithItems | NavItemPropsWithItems)[], level + 1)}
                             </SubNav>
                         );
                     } else {
@@ -424,4 +424,4 @@ class Nav extends BaseComponent<NavProps, NavState> {
     }
 }
 
-export default Nav;
+export default Nav;