chore: Update main.yml

Author: ezcolin2

.github/workflows/main.yml

@@ -41,4 +41,4 @@ jobs:
       # 빌드 및 파일 복사
       - name: Copy files to /home/root/app directory
         run: |
-          scp -o StrictHostKeyChecking=no -r ./dist/ ${{ secrets.REMOTE_USER }}@${{ secrets.REMOTE_IP }}:/home/root/app 
+          scp -o StrictHostKeyChecking=no -r ./backend/dist/ ${{ secrets.REMOTE_USER }}@${{ secrets.REMOTE_IP }}:/home/root/app