Remove link to polyfill.io

[westonruter]

The polyfill.io domain has been hijacked in a supply chain attack. While we don't seem to be pulling anything from the domain, we are linking to it. This link should be removed.

See:

• https://thehackernews.com/2024/06/over-110000-websites-affected-by.html
• https://www.theregister.com/2024/06/25/polyfillio_china_crisis/
• https://www.bleepingcomputer.com/news/security/polyfillio-javascript-supply-chain-attack-impacts-over-100k-sites/

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Co-authored-by: westonruter <westonruter@git.wordpress.org>
Co-authored-by: ockham <bernhard-reiter@git.wordpress.org>
Co-authored-by: ellatrix <ellatrix@git.wordpress.org>

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[ockham]

Thank you!

[ellatrix]

Could we link to the npm package instead?

[ellatrix]

Whoops, sorry missed the previous approval.

Looks like it's coming from here:

https://github.com/WordPress/wordpress-develop/blob/36e6d98a228729c2993b3c7921d9a31efca55d0a/tools/webpack/packages.js#L88

https://www.npmjs.com/package/polyfill-library