Update index.md

[duonghoanghai]

Why:

Closes [issue link]

What's being changed:

Check off the following:

• I have reviewed my changes in staging (look for the latest deployment event in your pull request's timeline, then click View deployment).
• For content changes, I have completed the self-review checklist.

Writer impact (This section is for GitHub staff members only):

• This pull request impacts the contribution experience
  • I have added the 'writer impact' label
  • I have added a description and/or a video demo of the changes below (e.g. a "before and after video")

[welcome]

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[duonghoanghai]

Sắp vào hoạt ₫ộng. Inc chúng ta... Vì tôi mất rất nhiều thủ tục xác thực ỡ Việt Nam... 7 ngày nữa sẽ trình làng sương sườn l-f