[ko]: revise index.md in web/http/authentication

[IMHOJEONG]

Description

#15393 을 통해 관리되는 PR 입니다. web/http/authentication을 번역하였습니다.

Motivation

web/http 폴더를 전체 번역해보고 싶었습니다. 발표 때 좋은 아이디어를 공유받아서 시작하게 되었습니다!

Additional details

Related issues and pull requests

#14965
#15393

[github-actions]

Preview URLs

• /ko/docs/Web/HTTP/Authentication

Flaws (1)

URL: /ko/docs/Web/HTTP/Authentication
Title: HTTP 인증
Flaw count: 1

• macros:
  • /ko/docs/Glossary/challenge does not exist but fell back to /en-US/docs/Glossary/Challenge

External URLs (7)

URL: /ko/docs/Web/HTTP/Authentication
Title: HTTP 인증

• https://bugzil.la/1419658 (1 time) (Note! This may be a new URL 👀)
• https://bugzil.la/1423146 (1 time) (Note! This may be a new URL 👀)
• https://crbug.com/82250 (1 time) (Note! This may be a new URL 👀)
• https://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-auth-using-authorization-header.html (1 time) (Note! This may be a new URL 👀)
• https://httpd.apache.org/docs/2.4/misc/password_encryptions.html (1 time) (Note! This may be a new URL 👀)
• https://www.iana.org/assignments/http-authschemes/http-authschemes.xhtml (1 time) (Note! This may be a new URL 👀)
• https://www.ietf.org/rfc/rfc4559.txt (1 time) (Note! This may be a new URL 👀)