Bump django from 3.2.3 to 3.2.4 in /testing/plugins_integration

Bumps [django](https://github.com/django/django) from 3.2.3 to 3.2.4.
- [Release notes](https://github.com/django/django/releases)
- [Commits](https://github.com/django/django/compare/3.2.3...3.2.4)

---
updated-dependencies:
- dependency-name: django
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

testing/plugins_integration/requirements.txt

@@ -1,5 +1,5 @@
 anyio[curio,trio]==3.1.0
-django==3.2.3
+django==3.2.4
 pytest-asyncio==0.15.1
 pytest-bdd==4.0.2
 pytest-cov==2.12.0