Bump @babel/core from 7.12.9 to 8.0.1 in /site-ui

Bumps [@babel/core](https://github.com/babel/babel/tree/HEAD/packages/babel-core) from 7.12.9 to 8.0.1.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/main/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/commits/v8.0.1/packages/babel-core)

---
updated-dependencies:
- dependency-name: "@babel/core"
  dependency-version: 8.0.1
  dependency-type: indirect
...

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

Author: dependabot[bot]