Update Dockerfile

Fixed environment variable PATH syntax in Dockerfile

docker/Dockerfile

@@ -40,7 +40,7 @@ RUN conda init bash
 
 # create and activate conda environment
 RUN conda create -n hunyuan3d21 python=3.10 && echo "source activate hunyuan3d21" > ~/.bashrc
-ENV PATH /workspace/miniconda3/envs/hunyuan3d21/bin:$PATH
+ENV PATH="/workspace/miniconda3/envs/hunyuan3d21/bin:${PATH}"
 
 # Set conda to always auto-approve
 RUN conda config --set always_yes true