fix, sciter, reconnect, check thread running before the state

Signed-off-by: fufesou <shuanglongchen@yeah.net>

src/ui_session_interface.rs

@@ -888,11 +888,13 @@ impl<T: InvokeUiSession> Session<T> {
         // 2. If the connection is established, send `Data::Close`.
         // 3. If the connection is disconnected, do nothing.
         let mut connection_round_state_lock = self.connection_round_state.lock().unwrap();
+        if self.thread.lock().unwrap().is_some() {
             match connection_round_state_lock.state {
                 ConnectionState::Connecting => return,
                 ConnectionState::Connected => self.send(Data::Close),
                 ConnectionState::Disconnected => {}
             }
+        }
         let round = connection_round_state_lock.new_round();
         drop(connection_round_state_lock);