Drop babel-polyfill

[Yaytay]

Describe the bug
formio/react depends on "babel-polyfill": "^6.26.0", the current page for babel-polyfill states that "As of Babel 7.4.0, this package has been deprecated in favor of directly including core-js/stable"
Can formio/react drop babel-polyfill?

The dependency on an old version of babel-polyfill drags in an old version of core-js (2.6.12) that comes with scary performance warnings.