This release mainly contains a bump of the engine.io and ws packages, but no additional features.

Links:

• Milestone: 2.3.0
• Diff: https://github.com/socketio/socket.io/compare/2.2.0...2.3.0
• Client release: 2.3.0
• engine.io version: ~3.4.0 (diff: https://github.com/socketio/engine.io/compare/3.3.1...3.4.2)
• ws version: ^7.1.2 (diff: https://github.com/websockets/ws/compare/6.1.2...7.3.1)