test: use Docker for playwright tests

tests/app/page.spec.ts

@@ -1,10 +1,6 @@
 import { expect, test } from "@playwright/test";
 
-// avoid VRT on CI because of difference between CI and local test env
-// we can do VRT on CI if dockerize local test env
-if (!process.env.CI) {
-  test("VRT", async ({ page }) => {
-    await page.goto("/");
-    await expect(page).toHaveScreenshot();
-  });
-}
+test("VRT", async ({ page }) => {
+  await page.goto("/");
+  await expect(page).toHaveScreenshot();
+});