fixing indentation in pseudocode

Co-authored-by: Junho Choi <1229714+junhochoi@users.noreply.github.com>

draft-ietf-quic-recovery.md

@@ -1530,7 +1530,7 @@ newly acked_packets from sent_packets.
     // Do not increase congestion_window if application
     // limited or flow control limited.
     if (IsAppOrFlowControlLimited())
-        return
+      return
 
     // Do not increase congestion window in recovery period.
     if (InCongestionRecovery(acked_packet.time_sent)):