fix(ci): use native fetch in OG image check script

Removed node-fetch dependency to fix ERR_MODULE_NOT_FOUND in CI.

scripts/check-og-images.ts

@@ -1,4 +1,3 @@
-import fetch from 'node-fetch';
 import { SITE_URL } from '../lib/schema.js';
 
 const BASE_URL = process.env.TEST_URL || SITE_URL;