fix docker compose

.devcontainer/devcontainer.json

@@ -1,6 +1,7 @@
 {
     "name": "Writer app",
-    "dockerFile": "Dockerfile",
+    "dockerComposeFile": "Dockerfile",
+    "service": "app",
     // Use 'appPort' to create a container with published ports. If the port isn't working, be sure
     // your server accepts connections from all interfaces (0.0.0.0 or '*'), not just localhost.
     "appPort": [