fix: ping not sent

v1/client/client.go

@@ -355,7 +355,7 @@ func (wsClient *SafeWebsocketClient) startPingTicker(ctx context.Context) {
 		case <-ticker.C:
 			wsClient.writeChan <- Message{
 				MessageType: websocket.PingMessage,
-				Data:        nil,
+				Data:        []byte{},
 			}
 		}
 	}