[i18n] Different links across languages

- For example in the vietnamese course, Giới thiệu(introduction) is converted as gii-thiu(good-natured) in the url.
Putting an english anchor should be necessary for all of the documentation regardless of language. This is because when people switch languages (from en->vi), the current system disallows them to see the same part of the documentation. This is troublesome for long api docs. Ideally, when a user makes a simple change in the language code, they will get to the section they want fast. What I am saying is:
- https://huggingface.co/course/en/chapter0/1#installing-dependencies
- https://huggingface.co/course/vi/chapter0/1#installing-dependencies
- https://huggingface.co/course/ko/chapter0/1#installing-dependencies
**should all point to the same location**. This is not the case now.
- Putting the burden on the translator doesn't seem right. **Anchoring in English can and should be done automatically**. I suggest a 2 step change to the documentation.
1. [x] Update the original English Documentation to include custom anchors by default for ease of translation by future contributors. https://github.com/huggingface/course/pull/380
2. [ ] Fix the currently translated documentation.

**May I please have some guidance on writing a fixing program for the currently translated documents?**

Note: Right-to-Left languages like Arabic have a unique linking structure, and I couldn't figure out where to put the custom anchor.

Thank you in advance for your review.