If you look at your URL, you'll see it doesn't match anything in the screenshot of the CDN's available URL's.
Try this:
https://cdnjs.cloudflare.com/ajax/libs/three.js/0.172.0/three.core.min.js
Did you get that malformed URL from the 'copy' button on the cloudflare site? If you did, you might need to report it as an error, it looks like they changed the way they construct the URL from the version number.
In future, you can also check an script source by just pasting the URL into the browser. It should open as plaintext javascript. If you do this with the busted URL you were using, you'll see that it returns a 404 page as HTML. This triggers a NS_ERROR_CORRUPTED_CONTENT
warning as a <script> tag import, because HTML content is not valid javascript content.