refactor(TenderDetails): enhance country flag handling and validation

- Updated the TenderDetails component to validate country codes using a new utility function, isValidAlpha2CountryCode.
- Modified the useGetFlagQuery hook to accept an options parameter for conditional fetching based on the validity of the country code.
- Improved the rendering logic for the country flag to ensure it only displays when valid flag data is available.

src/utils/shared.ts

@@ -110,3 +110,4 @@ export const deleteEmptyKeys = (obj: Record<string, any>) => {
   }
   return newObj;
 };
+export const isValidAlpha2CountryCode = (code: string) => /^[A-Za-z]{2}$/.test(code);