Bump djangorestframework from 3.15.1 to 3.15.2 in /requirements

Bumps [djangorestframework](https://github.com/encode/django-rest-framework) from 3.15.1 to 3.15.2.
- [Release notes](https://github.com/encode/django-rest-framework/releases)
- [Commits](encode/django-rest-framework@3.15.1...3.15.2)

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

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

requirements/requirements.txt

@@ -3,7 +3,7 @@ Whoosh==2.7.4
 argparse==1.2.1
 django-filter==24.2
 django-haystack==3.2.1
-djangorestframework==3.15.1
+djangorestframework==3.15.2
 cherrypy==18.8.0
 djangorestframework-csv==3.0.0
 django_compressor