Set DJANGO_SETTINGS_MODULE earlier in celery config

Moved the os.environ.setdefault call to ensure DJANGO_SETTINGS_MODULE is defined before importing Celery, which helps prevent potential configuration issues. This change enhances the reliability of the Celery application initialization process.

fbr/config/celery.py

@@ -1,11 +1,13 @@
+# flake8: noqa
+
 import os
 
+os.environ.setdefault("DJANGO_SETTINGS_MODULE", "config.settings.local")
+
 from celery import Celery
 from celery.schedules import crontab
 from dbt_copilot_python.celery_health_check import healthcheck
 
-os.environ.setdefault("DJANGO_SETTINGS_MODULE", "config.settings.local")
-
 celery_app = Celery("fbr_celery")
 
 celery_app.config_from_object("fbr.config.settings.local", namespace="CELERY")