fix: Ignore docker image prune race in demo deploy (#2136)

docker image prune -f fails with "a prune operation is already
running" when another prune is in flight (e.g. from a previous
deploy or a cron job). This is a best-effort cleanup step - if it
fails the deploy is still valid. Add || true so the step does not
abort the pipeline.

Co-authored-by: Ben Coombs <bjcoombs@users.noreply.github.com>

Author: bjcoombs

.github/workflows/deploy-demo.yml

@@ -229,7 +229,7 @@ jobs:
             echo "All services running"
 
             docker compose exec -T caddy caddy reload --config /etc/caddy/Caddyfile
-            docker image prune -f
+            docker image prune -f || true
 
       - name: Ensure databases exist
         uses: appleboy/ssh-action@0ff4204d59e8e51228ff73bce53f80d53301dee2 # v1.2.5