Fixes https://github.com/spring-projects/spring-integration/issues/3744 The `ServerWebSocketContainer.stop()` accidentally calls `this.handshakeHandler.start()` **Cherry-pick to `5.5.x`**
Fixes https://github.com/spring-projects/spring-integration/issues/3744 The `ServerWebSocketContainer.stop()` accidentally calls `this.handshakeHandler.start()` **Cherry-pick to `5.5.x`**