Prior to this change, duplicate SubProtocolHandlers could be registered
when configuring STOMP with several registrations:
public void registerStompEndpoints
(final StompEndpointRegistry registry) {
this.endpointRegistry.addEndpoint("/stompOverWebSocket");
this.endpointRegistry.addEndpoint("/stompOverSockJS").withSockJS();
}
This commit registers sub-protocols in a Set instead of a list (see
SubProtocolWebSocketHandler), thus fixing the issue.
Issue: SPR-12403
1fff631daa