Bump babel-plugin-polyfill-corejs2 from 0.4.7 to 0.4.8 in /src/Client

Bumps [babel-plugin-polyfill-corejs2](https://github.com/babel/babel-polyfills/tree/HEAD/packages/babel-plugin-polyfill-corejs2) from 0.4.7 to 0.4.8.
- [Commits](https://github.com/babel/babel-polyfills/commits/babel-plugin-polyfill-corejs2@0.4.8/packages/babel-plugin-polyfill-corejs2)

---
updated-dependencies:
- dependency-name: babel-plugin-polyfill-corejs2
  dependency-type: indirect
  update-type: version-update:semver-patch
...

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