Fix Docker deployment - use built image instead of building locally

- Change docker-compose.prod.yml to use ghcr.io image instead of building
- Add --force-recreate flag to ensure new container is created
- Add docker image prune to remove old images
- This should fix the issue where old container version is served

docker-compose.prod.yml

@@ -1,8 +1,6 @@
 services:
   portfolio:
-    build:
-      context: .
-      dockerfile: Dockerfile
+    image: ghcr.io/denshooter/my_portfolio:production
     container_name: portfolio-app
     restart: unless-stopped
     ports: