how to edit resourceHints links from bigcommerce?

I need bit of help here as I don't know where to edit {{resourceHints}} files which automatically added to top section of bigcommerce website.

I also found this resource from BigCommerce but don't know what to do further from here: bigcommerce resourceHints

Why I want to edit them? - Because google crawler doing crawling to the site and its detecting 404 page from below link:

<link rel="dns-prefetch preconnect" href="https://fonts.googleapis.com/" crossorigin>

Now to avoid google to crawling the above link I need to add "nofollow" attribute to rel of the above line. So that google doesn't try to go to this external link and mark them as 404 page not found list.

OR if anyone know how to add this in robots.txt file so that the above links are not getting crawl by google. OR how to fix this by any other way.

Thanks in advance and if you've any question regarding this to me then please let me know.

I just remove that line and add my own hints directly to the code.

For robots.txt editing, go into admin->settings and search for "robots". Select the "Website" option, and scroll down to the editor.

It's quite strange that Google is picking up that link and crawling it. Where is it reporting them as 404 pages?