🌐 [i18n-KO] Translated `tutorial/proprecssing.mdx` to Korean
Author: sim-so
Pull request: yes

# What does this PR do?

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Translated ~partially~ the documentation `tutorial/proprecessing.mdx` to Korean.
- [x] Proprecessing 전처리
  - [x] Natural Language Processing 자연어처리
    - [x] Pad 패딩
    - [x] Trancation 생략
    - [x] Build Tensor 텐서 만들기
  - [x] Audio 오디오
  - [x] Computer Vision 컴퓨터 비전
    - [x] Pad 패딩
  - [x] Multimodal 멀티모달

Thank you in advance for your review!

Part of #20179 

## Before submitting
- [x] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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      Pull Request section?
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      [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?

Team PsedoLab, could you review this PR?

@wonhyeongseo @0525hhgus @kihoon71 @gabrielwithappy, @HanNayeoniee, @jungnerd 

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Models:

- text models: @ArthurZucker and @younesbelkada
- vision models: @amyeroberts
- speech models: @sanchit-gandhi
- graph models: @clefourrier

Library:

- flax: @sanchit-gandhi
- generate: @gante
- pipelines: @Narsil
- tensorflow: @gante and @Rocketknight1
- tokenizers: @ArthurZucker
- trainer: @sgugger

Integrations:

- deepspeed: HF Trainer: @stas00, Accelerate: @pacman100
- ray/raytune: @richardliaw, @amogkam

Documentation: @sgugger, @stevhliu and @MKhalusova

HF projects:

- accelerate: [different repo](https://github.com/huggingface/accelerate)
- datasets: [different repo](https://github.com/huggingface/datasets)
- diffusers: [different repo](https://github.com/huggingface/diffusers)
- rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)

Maintained examples (not research project or legacy):

- Flax: @sanchit-gandhi
- PyTorch: @sgugger
- TensorFlow: @Rocketknight1

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Comments:
_The documentation is not available anymore as the PR was closed or merged._

@sim-so keep it up 👍 :-)


Some updates!
- Newly translated two parts of this documentation: `Build Tensors` and `Audio`
- Revised the sentence with the feedback as below:
`토크나이저가 두 개의 특수한 토큰(분류 토큰 CLS와 구분 토큰 SEP)을 문장에 추가했습니다.`
- Translated and revised all `feature extractor` to `특징 추출기` based on TTA.

I am going to finish it by this Sunday. Thank you all in advance! :smile:

I translated all of this document.
Thank you in advance for your review! 😉 

다른 문서들을 참고하여 일부 단어의 번역어를 모두 변경했습니다.
- argument -> 인수
- feature extractor -> 특성 추출기
- method -> 메소드
- separator([SEP]) -> 분할 토큰

Could you review this PR?
@sgugger, @ArthurZucker, @eunseojo