Create tests: dumps message, "retry" (#281)

e2e-tests/1.spec.ts

@@ -0,0 +1,9 @@
+import { expect } from "@playwright/test";
+import { test } from "./helpers/test_helper";
+
+test("renders the first page", async ({ electronApp }) => {
+  const page = await electronApp.firstWindow();
+  await page.waitForSelector("h1");
+  const text = await page.$eval("h1", (el) => el.textContent);
+  expect(text).toBe("Build your dream app");
+});