Bump react-scripts from 4.0.1 to 4.0.3 in /webapp

Bumps [react-scripts](https://github.com/facebook/create-react-app/tree/HEAD/packages/react-scripts) from 4.0.1 to 4.0.3.
- [Release notes](https://github.com/facebook/create-react-app/releases)
- [Changelog](https://github.com/facebook/create-react-app/blob/master/CHANGELOG.md)
- [Commits](https://github.com/facebook/create-react-app/commits/[email protected]/packages/react-scripts)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]