Vapor: 4.33.0 Release

This patch was authored by @code28 and released by @siemensikkema.

Adds support for a custom implementation of shouldUpgrade for websockets. This can be used to switch to specific subprotocols or to deny upgrading by returning nil.

routes.webSocket("authedecho", shouldUpgrade: { req in
    guard req.auth.has(User.self) else {
        return req.eventLoop.future(nil)
    }
    return req.eventLoop.future([:])            
}, onUpgrade: { req, ws in
    print(ws)
})