🌐 [i18n-KO] Update README_ko.md

[J4BEZ]

Delete the blank paragraph in the language selection button and Edit to synchronize with the English version of README.md

What does this PR do?

Delete an empty paragrah under the language selection by removing white space. And synchronize README_ko.md to README.md.

• [x] Additional edit for keep consistency with main documentation. (메인 문서와 일관성 유지를 위한 수정)
• [x] Grammar Check (맞춤법 검사)

• Maintain the content of the existing document as much as possible.
• Juxtapose in English of some tasks.

There could be mistranslations or awkwardness. If you found any of them, I would appreciate it if you could correct the error to make the community shine🙇‍♂️

Thanks for your hard effort that everyone can enjoy thousands of models and learn DL more easily!

I'm sorry to find this PR late #20179 (굉장히 좋은 가이드가 있었군요! 늦게 확인해서 죄송합니다😅)

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, Pull Request section?
• [ ] Was this discussed/approved via a Github issue or the forum? Please add a link to it if that's the case.
• [ ] Did you make sure to update the documentation with your changes? Here are the documentation guidelines, and here are tips on formatting docstrings.
• [ ] Did you write any new necessary tests?

Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag members/contributors who may be interested in your PR.