fix: robots 파일 base url 변경

Author: ShipFriend0516

app/robots.ts

@@ -2,7 +2,7 @@
 import { MetadataRoute } from 'next';
 
 export default function robots(): MetadataRoute.Robots {
-  const baseURL = process.env.NEXTAUTH_URL || 'http://localhost:3000';
+  const baseURL = process.env.NEXT_PUBLIC_DEPLOYMENT_URL || process.env.NEXTAUTH_URL || 'http://localhost:3000';
   return {
     rules: {
       userAgent: '*',