udpate docs

Author: YifuTao

README.md

@@ -16,6 +16,7 @@ Build a docker image to install dependencies and run SiLVR.
 ```
 docker compose -f .docker/docker_compose.yaml run --build silvr
 ```
+Note: You can use your own `CUDA_ARCHITECTURES` in the Dockerfile to make the `tinycudann` build quicker.
 ### Manual Installation
 You can also install SiLVR to your system manually.
 ```