🌐 [i18n-KO] Translated `tasks/summarization.mdx` to Korean

[sim-so]

What does this PR do?

Translated the tasks/summarization.mdx file of the documentation to Korean. 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).
• [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.
• [x] 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?

This is a work on progress. Could you review this PR when I finish this work? @0525hhgus, @KIHOON71, @sim-so, @gabrielwithappy, @HanNayeoniee, @wonhyeongseo, @jungnerd

[sim-so]

Team Pseudo Lab, I'm happy to inform you I finished the translation! Could you review this PR?

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[sim-so]

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