Part5d(en): Fix Playwright describe and beforeEach examples

[Okamissu]

What changed

This PR updates the Playwright examples to use Playwright Test helpers through the test object:

• test.describe(...)
• test.beforeEach(...)

The examples now import only test and expect from @playwright/test.

Why

The current examples destructure helpers like describe and beforeEach directly from @playwright/test, for example:

const { test, describe, expect } = require('@playwright/test')

and:

const { test, expect, beforeEach } = require('@playwright/test')

However, the Playwright docs document these APIs as methods on the test object:

• test.describe
• test.beforeEach

The docs also show examples importing test and expect from @playwright/test, then calling test.describe(...) and test.beforeEach(...).

Using the documented form makes the examples clearer and avoids confusion for learners who will run into describe or beforeEach being undefined.

Example

Before:

const { test, describe, expect } = require('@playwright/test')

describe('Note app', () => {
  test('front page can be opened', async ({ page }) => {
    // ...
  })
})

After:

const { test, expect } = require('@playwright/test')

test.describe('Note app', () => {
  test('front page can be opened', async ({ page }) => {
    // ...
  })
})

Before:

const { test, expect, beforeEach } = require('@playwright/test')

beforeEach(async ({ page }) => {
  await page.goto('http://localhost:5173')
})

After:

const { test, expect } = require('@playwright/test')

test.beforeEach(async ({ page }) => {
  await page.goto('http://localhost:5173')
})

Scope

This PR only updates Playwright API usage in the course material. It does not change the test logic, exercise requirements, or expected application output.