[Docs]: deprecated field order description

[urlyy]

Current State

Description of the current issue:
only need one clear description.

Link to the page, allows developers to better identify problems:
https://fory.apache.org/docs/specification/fory_xlang_serialization_spec#struct

Screenshots (if relevant):

Desired State

No response

Would you like to fix this issue?

None

[Abhinandankaushik]

@urlyy hey i want to work on this issue can you assign it to me so i will work on int

[urlyy]

@chaokunyang Does this part of the document still need to be revised?

[SONAM-git99]

@urlyy Hi, I would like to work on this issue. I can update the documentation to clarify the deprecated field order description. Please let me know if that works.