[chore] Release 2.3.0
[chore] Release 2.3.0

Diff: https://github.com/socketio/socket.io/compare/2.2.0...2.3.0

socketio/socket.io,mosoft521/socket.io,Automattic/socket.io,mosoft521/socket.io,socketio/socket.io,SimenB/socket.io,Automattic/socket.io