Move tutorial Docker service to own compose file again

This is due to VSCode not supporting docker profiles (yet?).
Thus we have issues setting up a nice DevContainer that doesn't start the demo as well.

demo/docker-compose.tutorial.yaml

@@ -0,0 +1,13 @@
+services:
+  tutorial:
+    image: ghcr.io/kit-mrt/arbitration_graphs_pacman_tutorial:$VERSION
+    env_file: .env
+    ports:
+      - "8080:8080"
+    volumes:
+      - .:/home/blinky/demo
+      - $HOME/.Xauthority:/home/blinky/.Xauthority
+      - /tmp/.X11-unix:/tmp/.X11-unix
+    environment:
+      - DISPLAY=$DISPLAY
+

demo/docker-compose.yaml

@@ -1,15 +1,8 @@
 services:
   tutorial:
-    image: ghcr.io/kit-mrt/arbitration_graphs_pacman_tutorial:$VERSION
-    env_file: .env
-    ports:
-      - "8080:8080"
-    volumes:
-      - .:/home/blinky/demo
-      - $HOME/.Xauthority:/home/blinky/.Xauthority
-      - /tmp/.X11-unix:/tmp/.X11-unix
-    environment:
-      - DISPLAY=$DISPLAY
+    extends:
+      file: docker-compose.tutorial.yaml
+      service: tutorial
     #
     # This makes sure `docker compose up` only runs the demo service
     # Use `docker compose run --rm --service-ports tutorial` to run the tutorial