chore: CI/CD workflow 변경된 AWS EC2 환경에 맞춰 script 수정

.github/workflows/ci-cd.yml

@@ -50,7 +50,7 @@ jobs:
           username: ${{ secrets.AWS_EC2_USERNAME }}
           key: ${{ secrets.AWS_EC2_KEY_PROD }}
           script: |
-            cd /home/ubuntu/backend
+            cd /home/ec2-user/fmr/server-main/
             sudo docker compose down
             sudo docker pull ${{ secrets.DOCKER_REPO_PROD }}
             sudo docker compose up -d