Bumps [socket.io](https://github.com/socketio/socket.io) from 2.3.0 to 2.4.0. - [Release notes](https://github.com/socketio/socket.io/releases) - [Changelog](https://github.com/socketio/socket.io/blob/2.4.0/CHANGELOG.md) - [Commits](https://github.com/socketio/socket.io/compare/2.3.0...2.4.0) Signed-off-by: dependabot[bot] <support@github.com>