test: update test to not use createRawSnippet, use test component instead

tests/unit/routes/page.test.ts

@@ -0,0 +1,11 @@
+import { render, screen } from "@testing-library/svelte";
+import { describe, expect, it } from "vitest";
+import PageTest from "./PageTest.svelte";
+
+describe("+page.svelte", () => {
+  it("should render without crashing", () => {
+    render(PageTest);
+    const mainGrid = document.querySelector(".main-grid");
+    expect(mainGrid).toBeInTheDocument();
+  });
+});