Fix rumqttc build with websocket feature enabled

[MightyPork]

This is a fix for building rumqttc with the websocket feature enabled.

Note that the Cargo.lock in the workspace is hopelessly outdated and build fails, so I locally had to do cargo update first. That is not included in the PR.

error[E0277]: the trait bound `WebSocketStream<S>: futures_sink::Sink<Message>` is not satisfied
   --> /home/ondra/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/ws_stream_tungstenite-0.14.0/src/tung_websocket.rs:145:53
    |
145 |         if ready!( Pin::new( &mut self.closer ).run( &mut self.inner, &mut self.notifier, cx) ).is_err()
    |                                                 ---       ^^^^^^^^^^ the trait `futures_sink::Sink<Message>` is not implemented for `WebSocketStream<S>`
    |                                                 |
    |                                                 required by a bound introduced by this call
    |
    = help: the following other types implement trait `futures_sink::Sink<Item>`:
              `&futures_channel::mpsc::UnboundedSender<T>` implements `futures_sink::Sink<T>`
              `&mut S` implements `futures_sink::Sink<Item>`
              `Box<S>` implements `futures_sink::Sink<Item>`
              `Buffer<Si, Item>` implements `futures_sink::Sink<Item>`
              `BufferUnordered<S>` implements `futures_sink::Sink<Item>`
              `Buffered<S>` implements `futures_sink::Sink<Item>`
              `Either<A, B>` implements `futures_sink::Sink<Item>`
              `Fanout<Si1, Si2>` implements `futures_sink::Sink<Item>`
            and 60 others
    = note: required for `&mut WebSocketStream<S>` to implement `futures_sink::Sink<Message>`
note: required by a bound in `Closer::run`
   --> /home/ondra/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/ws_stream_tungstenite-0.14.0/src/tung_websocket/closer.rs:95:21
    |
 92 |     pub(super) fn run
    |                   --- required by a bound in this associated function
...
 95 |         mut socket : impl Sink<tungstenite::Message, Error=TungErr> + Unpin ,
    |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Closer::run`

[giridher-art]

hey @MightyPork , can you specify the details of how the does this error occurs ? is this specific to a feature ?

[MightyPork]

I just enabled the websocket feature and it failed to build, even standalone outside my project. We are now switched to my fork before this is fixed upstream.

#rumqttc = { version = "0.25", features = ["proxy", "websocket"] } # version = "0.25.0",
rumqttc = { git = "https://github.com/MightyPork/rumqtt", branch = "fix-websocket-build", features = ["proxy", "websocket"] } # version = "0.25.0",

[giridher-art]

@MightyPork we will cut a new release .