[Doc-17212] Enhance HTTP task documentation overview section in both Chinese and English

[MicroYui]

Purpose of the pull request

close #17212

Improve the HTTP task documentation by enhancing the overview section with more detailed descriptions and clearer explanations of use cases in both Chinese and English versions.

Brief change log

• Enhanced the overview section of HTTP task documentation in Chinese (docs/docs/zh/guide/task/http.md)
• Enhanced the overview section of HTTP task documentation in English (docs/docs/en/guide/task/http.md)
• Added more detailed descriptions of HTTP task capabilities and common use cases
• Improved readability and clarity of the documentation for better user guidance

Verify this pull request

This pull request is code cleanup without any test coverage.

This change is a documentation improvement that can be verified by:

• Reviewing the enhanced overview sections in both language versions for clarity and accuracy
• Ensuring the documentation follows the project's documentation standards
• Confirming that the modified content provides better guidance for users in both Chinese and English

[boring-cyborg[bot]]

Thanks for opening this pull request! Please check out our contributing guidelines. (https://github.com/apache/dolphinscheduler/blob/dev/docs/docs/en/contribute/join/pull-request.md)