Update opportunities-api.md

[maheshamuthukuda]

Add new validation error messages for Award Amount.

[angjenkins]

---------- Forwarded message ---------
From: Ali Talib - IDQAB ali.talib@gsa.gov
Date: Wed, Dec 13, 2023 at 9:50 AM
Subject: Re: Opportunity Management API documentation update(repo: open-gsa-redesign )
To: Mahesha Muthukuda Arachchilage - QD2-C mahesha.muthukudaarachchilage@gsa.gov
Cc: Timothy Hawes - IDQAB timothy.hawes@gsa.gov, Angelica Jenkins - IDQBC angelica.jenkins@gsa.gov, Chirdeep Sharma - QD2-C chirdeep.sharma@gsa.gov, Joshua Zigler - Q2ACB joshua.zigler@gsa.gov, Kay Kwaven - QD2-C kay.kwaven@gsa.gov, Kamoliddin Hamzayev - QD2-C kamoliddin.hamzayev@gsa.gov

Approved.

Thank You,

Talib Ali Asger M
GSA-IT, IQ
703-408-6136