BuiltWith API returns 'text/json; charset=utf-8' as the Content-Type
header instead of 'application/json'. aiohttp's response.json() raises
a ContentTypeError by default when the MIME type is not application/json.
Passing content_type=None tells aiohttp to skip the content-type check
and parse the response body as JSON regardless of the declared MIME type.
Fixes#2235
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
