Bump http-proxy-middleware and react-scripts in /frontend

Bumps [http-proxy-middleware](https://github.com/chimurai/http-proxy-middleware) and [react-scripts](https://github.com/facebook/create-react-app/tree/HEAD/packages/react-scripts). These dependencies needed to be updated together.

Updates `http-proxy-middleware` from 1.0.4 to 3.0.3
- [Release notes](https://github.com/chimurai/http-proxy-middleware/releases)
- [Changelog](https://github.com/chimurai/http-proxy-middleware/blob/master/CHANGELOG.md)
- [Commits](chimurai/http-proxy-middleware@v1.0.4...v3.0.3)

Updates `react-scripts` from 3.4.1 to 5.0.1
- [Release notes](https://github.com/facebook/create-react-app/releases)
- [Changelog](https://github.com/facebook/create-react-app/blob/main/CHANGELOG-3.x.md)
- [Commits](https://github.com/facebook/create-react-app/commits/react-scripts@5.0.1/packages/react-scripts)

---
updated-dependencies:
- dependency-name: http-proxy-middleware
  dependency-type: direct:production
- dependency-name: react-scripts
  dependency-type: direct:production
...

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