chore : cicd pipeline 수정

#1

.github/workflows/ci-cd-pipeline.yml

@@ -26,7 +26,7 @@ jobs:
       # Create and activate virtual environment, install dependencies
       - name: Install dependencies
         run: |
-          python -m venv venv
+          cd backend
           source venv/bin/activate
           pip install --upgrade pip
           pip install -r requirements.txt