fix(FN-4245): use package-relative path in CSS token test

Fusion-Task-Id: FN-4245
Fusion-Task-Lineage: 7b816bdb-e848-4ca3-b74f-9e4ce696ce06

packages/dashboard/app/components/__tests__/FileBrowser.css.test.ts

@@ -3,8 +3,7 @@ import { describe, expect, it } from "vitest";
 
 describe("FileBrowser.css token contract", () => {
   it("does not use deprecated --radius alias token", async () => {
-    const cssPath = new URL("../FileBrowser.css", import.meta.url);
-    const css = await readFile(cssPath, "utf8");
+    const css = await readFile("app/components/FileBrowser.css", "utf8");
     expect(css).not.toMatch(/var\(--radius\)/);
   });
 });