🌐 [i18n-KO] Translated `contributing.md` to Korean
Author: mjk0618
Pull request: yes

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# What does this PR do?

Translated the `contributing.md` file of the documentation to Korean.
Thank you in advance for your review. 

Part of https://github.com/huggingface/transformers/issues/20179

## Before reviewing
- [x] Check for missing / redundant translations (번역 누락/중복 검사)
- [x] Grammar Check (맞춤법 검사)
- [x] Review or Add new terms to glossary (용어 확인 및 추가)
- [x] Check Inline TOC (e.g. `[[lowercased-header]]`)
- [ ] Check live-preview for gotchas (live-preview로 정상작동 확인)

## Who can review? (Initial)
@bolizabeth, @nuatmochoi, @heuristicwave, @mjk0618, @keonju2, @harheem, @HongB1, @junejae, @54data, @seank021, @augustinLib, @sronger, @TaeYupNoh, @kj021, @eenzeenee 
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## Before submitting
- [x] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
- [x] Did you read the [contributor guideline](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md#start-contributing-pull-requests),
      Pull Request section?
- [ ] Was this discussed/approved via a Github issue or the [forum](https://discuss.huggingface.co/)? Please add a link
      to it if that's the case.
- [x] Did you make sure to update the documentation with your changes? Here are the
      [documentation guidelines](https://github.com/huggingface/transformers/tree/main/docs), and
      [here are tips on formatting docstrings](https://github.com/huggingface/transformers/tree/main/docs#writing-source-documentation).
- [ ] Did you write any new necessary tests?

## Who can review? (Final)
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May you please review this PR? @sgugger, @ArthurZucker, @eunseojo

Comments:
> Thanks for the translation! 🤗
> 
> Can you copy the contents of `CONTRIBUTING_ko.md` into `contributing.md`? We should just have one file for this.

Thank you for reviewing the translation!

In that case, should I delete the `CONTRIBUTING_ko.md` file in the root directory and just leave the `contributing.md` file in the `docs/source/ko` directory? The reason I added the `CONTRIBUTING_ko.md` file in the root directory is because the `contributing.md` file in the original English document had a different directory structure compared to the other documents.

Oh nevermind, I see what you mean! You can feel free to mark the PR as ready for review and we can merge!

> Oh nevermind, I see what you mean! You can feel free to mark the PR as ready for review and we can merge!

Thank you for your help! I marked the PR as ready for review. Could you please review and merge it?

May you please review this PR? @sgugger, @ArthurZucker, @eunseojo

@ArthurZucker, I think the `build_pr_documentation` test is failing because `docs/source/ko/contributing.md` is just a path to the actual docs and the [`generate_frontmatter_in_text`](https://github.com/huggingface/doc-builder/blob/c8152d4d1cb455e4b614dd34806f9c1345ad92b1/src/doc_builder/build_doc.py#L273) function is expecting a level 1 header. Would it still be ok to merge this PR?

@stevhliu would be better if we find a fix! It's my first time seeing this so not really sure

@stevhliu Thank you for reviewing my PR! Then, should I try to fix something so that the error does not occur? I think I have to  try to find out the reason for the error, if I can help fixing the problem. If it's something I can't do, would it be better to wait while translating other documents?

I think it's an issue with the test not recognizing the path to `contributing_ko.md` in the docs. We'll look into this issue, but in the meantime, feel free to keep up the good work translating other docs. This issue is probably only affecting this specific doc. 🙂 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_25877). All of your documentation changes will be reflected on that endpoint.

> Great work! Thanks for being patient and working with us on this 😄

Thank you so much for helping me complete this work successfully! Have a nice day!