Change CI django branch.

Author: WaVEV

.github/workflows/test-python.yml

@@ -30,8 +30,8 @@ jobs:
       - name: Checkout Django
         uses: actions/checkout@v4
         with:
-          repository: 'mongodb-forks/django'
-          ref: 'mongodb-5.0.x'
+          repository: 'wavev/django'
+          ref: 'add-ObjectIdField'
           path: 'django_repo'
       - name: Install system packages for Django's Python test dependencies
         run: |