fix: examples/django/requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-DJANGO-12485156

Author: snyk-bot

examples/django/requirements.txt

@@ -1,3 +1,3 @@
-django>=2.2.1
+django>=4.2.24
 sqlalchemy>=1.0.14
 celery>=5.0.5