Fix api contract for Post /requests endpoint of OOO requests

[surajmaity1]

Issue Description

Fix the OOO request information for the POST /requests endpoint.

Expected Behavior

• Rename message to reason field and removed state field from OOO's request body.
• Update response body of OOO request
• Add error responses.

Reproducibility

• This issue is reproducible
• This issue is not reproducible

Severity/Priority

• Critical
• High
• Medium
• Low

Checklist

• I have read and followed the project's code of conduct.
• I have searched for similar issues before creating this one.
• I have provided all the necessary information to understand and reproduce the issue.
• I am willing to contribute to the resolution of this issue.

[JC-Coder]

@surajmaity1 still working on this ?