fix: deploy script missing backend

Author: Smaug6739

.github/workflows/deploy_to_prod.yml

@@ -86,7 +86,7 @@ jobs:
         run: |
           rsync -avz  --delete --force --exclude 'server/node_modules' -e "ssh -i deploy_key" frontend/.output ${SSH_USER}@${SSH_HOST}:${REMOTE_PATH}/frontend
           rsync -avz --delete --force -e "ssh -i deploy_key" ecosystem.config.js ${SSH_USER}@${SSH_HOST}:${REMOTE_PATH}
-          rsync -avz --delete --force -e "ssh -i deploy_key" backend/backend_app
+          rsync -avz --delete --force -e "ssh -i deploy_key" backend/backend_app ${SSH_USER}@${SSH_HOST}:${REMOTE_PATH}/backend
           rsync -avz --delete --force -e "ssh -i deploy_key" .env.production ${SSH_USER}@${SSH_HOST}:${REMOTE_PATH}/.env.production
       - name: Install frontend dependencies on server
         run: |