Bump socket.io from 2.2.0 to 2.4.1 in /story-app

Bumps [socket.io](https://github.com/socketio/socket.io) from 2.2.0 to 2.4.1.
- [Release notes](https://github.com/socketio/socket.io/releases)
- [Changelog](https://github.com/socketio/socket.io/blob/2.4.1/CHANGELOG.md)
- [Commits](socketio/socket.io@2.2.0...2.4.1)

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Author: dependabot[bot]