fix: cancel netconn contexts after close handshake

netconn.go

@@ -115,10 +115,12 @@ type netConn struct {
 var _ net.Conn = &netConn{}
 
 func (nc *netConn) Close() error {
+	defer func() {
 		nc.writeTimer.Stop()
 		nc.writeCancel()
 		nc.readTimer.Stop()
 		nc.readCancel()
+	}()
 	return nc.c.Close(StatusNormalClosure, "")
 }