Update carla script to easier install docker and nvidia-docker (#23986)

* Easier docker and nvidia-docker install in carla script

* Small cleanup

* cleanuo

* cleanup

* More comments

* Remove adding usergroup step

tools/sim/start_carla.sh

@@ -2,16 +2,16 @@
 
 # Requires nvidia docker - https://github.com/NVIDIA/nvidia-docker
 if ! $(apt list --installed | grep -q nvidia-container-toolkit); then
-  if [ -z "$INSTALL" ]; then
-    echo "Nvidia docker is required. Re-run with INSTALL=1 to automatically install."
-    exit 0
-  else
+  read -p "Nvidia docker is required. Do you want to install it now? (y/n)";
+  if [ "${REPLY}" == "y" ]; then
     distribution=$(. /etc/os-release;echo $ID$VERSION_ID)
     echo $distribution
     curl -s -L https://nvidia.github.io/nvidia-docker/gpgkey | sudo apt-key add -
     curl -s -L https://nvidia.github.io/nvidia-docker/$distribution/nvidia-docker.list | sudo tee /etc/apt/sources.list.d/nvidia-docker.list
-    sudo apt-get update && sudo apt-get install -y nvidia-container-toolkit
+    sudo apt-get update && sudo apt-get install -y nvidia-docker2 # Also installs docker-ce and nvidia-container-toolkit
     sudo systemctl restart docker
+  else
+    exit 0
   fi
 fi