Fix unit test warnings (#13569)

Author: markdalgleish

packages/react-router-dev/__tests__/route-config-test.ts

@@ -1,5 +1,5 @@
 import path from "node:path";
-import { normalizePath } from "vite";
+import { normalize as normalizePath } from "pathe";
 
 import {
   validateRouteConfig,