MCKIN-17540: add korean translations

[msaqib52]

This PR adds korean translations

[openedx-webhooks]

Thanks for the pull request, @msaqib52! I've created OSPR-4599 to keep track of it in JIRA. JIRA is a place for product owners to prioritize feature reviews by the engineering development teams.

Feel free to add as much of the following information to the ticket:

• supporting documentation
• edx-code email threads
• timeline information ("this must be merged by XX date", and why that is)
• partner information ("this is a course on edx.org")
• any other information that can help Product understand the context for the PR

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