chore(deps-dev): bump @babel/polyfill from 7.4.3 to 7.8.3 (#447)

Bumps [@babel/polyfill](https://github.com/babel/babel) from 7.4.3 to 7.8.3.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.md)
- [Commits](babel/babel@v7.4.3...v7.8.3)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>