Fix ENVs to use "key=value" format

Author: amarburg

.docker/Dockerfile

@@ -211,6 +211,6 @@ RUN sudo apt-get update \
     && sudo rm -rf /var/lib/apt/lists/*
 
 # Env vars for the nvidia-container-runtime.
-ENV NVIDIA_VISIBLE_DEVICES all
-ENV NVIDIA_DRIVER_CAPABILITIES graphics,utility,compute
-ENV QT_X11_NO_MITSHM 1
+ENV NVIDIA_VISIBLE_DEVICES=all
+ENV NVIDIA_DRIVER_CAPABILITIES=graphics,utility,compute
+ENV QT_X11_NO_MITSHM=1