Replace deprecate @babel/polyfill package

[gziolo]

Extracted from #52854.

Related issues in Gutenberg repository with more details: ​https://github.com/WordPress/gutenberg/issues/22417.

According to ​https://babeljs.io/docs/en/babel-polyfill, @babel/polyfill got deprecated

It looks like we need to create a webpack entry point that imports core-js and regenerator-runtime.

import 'core-js/stable';
import 'regenerator-runtime/runtime';

They aren't defined as dependencies in package.json at the moment.

[ocean90]

Duplicate of #52941.

[gziolo]

I missed that. I commented on the ticket opened by @desrosj :)