core: 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]>

Author: dependabot[bot]

Diff for: pyproject.toml

@@ -24,7 +24,7 @@ dependencies = [
     "django-redis",
     "django-storages[s3]",
     "django-tenants",
-    "djangorestframework ==3.14.0",
+    "djangorestframework ==3.15.2",
     "djangorestframework-guardian",
     "docker",
     "drf-orjson-renderer",