⬆️ Bump djangorestframework from 3.14.0 to 3.15.2

Bumps [djangorestframework](https://github.com/encode/django-rest-framework) from 3.14.0 to 3.15.2.
- [Release notes](https://github.com/encode/django-rest-framework/releases)
- [Commits](encode/django-rest-framework@3.14.0...3.15.2)

---
updated-dependencies:
- dependency-name: djangorestframework
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements.txt

@@ -104,7 +104,7 @@ backports.tarfile==1.2.0  # needed by newer setuptools
 pysolr==3.10.0
 django-haystack==3.3.0
 requirements/src/django_audit_log-0.8.2-py2.py3-none-any.whl
-djangorestframework==3.14.0
+djangorestframework==3.15.2
 djangorestframework-jsonp==1.0.2
 Unidecode==1.3.2
 django-reversion==5.1.0