Use correct settings module for development

docker-compose.development.yml

@@ -6,6 +6,8 @@ services:
     build: &app-development-build
       target: development
     command: uv run --no-sync -- /app/src/manage.py runserver 0.0.0.0:8000
+    environment: &django-env
+      DJANGO_SETTINGS_MODULE: ${DJANGO_SETTINGS_MODULE:-newsreader.conf.docker}
     ports:
       - "${DJANGO_PORT:-8000}:8000"
     volumes:
@@ -17,6 +19,8 @@ services:
   celery:
     build:
       <<: *app-development-build
+    environment:
+      <<: *django-env
     volumes:
       - ./src/:/app/src