explicitly set config file

.github/workflows/main.yml

@@ -6,6 +6,11 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v2
+      - name: Set up environment variables
+        run: |
+          echo "DB_USER=${{ secrets.DB_USER }}" >> .env
+          echo "DB_PASSWORD=${{ secrets.DB_PASSWORD }}" >> .env
+          echo "DB_NAME=${{ secrets.DB_NAME }}" >> .env
       - name: Build and run Docker compose
         run: |
           docker-compose up -d