Revise blog on Tensor R-Fork usage

Author: amysaq2023

blog/2025-12-03-rfork.md

@@ -97,6 +97,7 @@ python -m sglang.launch_server [args] \
   --load-format remote_instance	\
   --remote-instance-weight-loader-seed-instance-ip [seed_instance_ip] \
   --remote-instance-weight-loader-seed-instance-service-port [seed_instance_service_port] \
+  --remote-instance-weight-loader-send-weights-group-ports [send_weights_nccl_group_ports_list]  \
   --remote-instance-weight-loader-backend nccl # optional, default is "nccl"
 ```