JIRA: https://jira.spring.io/browse/INT-3686
Since `WebSocketInboundChannelAdapter` is positioned as an adapter for WebSocket client side as well,
the appropriate Server-side frames should be handler properly there, too, even if `StompSubProtocolHandler`
isn't designed for the client side usage.
* Add catch of the `CONNECTED` and `RECEIPT` STOMP message types to the `WebSocketInboundChannelAdapter`
* Emit `CONNECTED` as a `SessionConnectedEvent`
* Emit `RECEIPT` as a new introduced `ReceiptEvent`
**Cherry-pick to 4.1.x**
More coverage for the new events stuff
f25a999ca5