Bump django from 2.2.21 to 3.2.24 in /demo

Bumps [django](https://github.com/django/django) from 2.2.21 to 3.2.24.
- [Commits](django/django@2.2.21...3.2.24)

---
updated-dependencies:
- dependency-name: django
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

demo/requirements.txt

@@ -1,2 +1,2 @@
-Django==2.2.21
+Django==3.2.24
 psycopg2-binary==2.8.2