Bump django-environ from 0.12.0 to 0.13.0

Bumps [django-environ](https://github.com/joke2k/django-environ) from 0.12.0 to 0.13.0.
- [Release notes](https://github.com/joke2k/django-environ/releases)
- [Changelog](https://github.com/joke2k/django-environ/blob/develop/CHANGELOG.rst)
- [Commits](joke2k/django-environ@v0.12.0...v0.13.0)

---
updated-dependencies:
- dependency-name: django-environ
  dependency-version: 0.13.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

pyproject.toml

@@ -9,7 +9,7 @@ license = "MIT"
 dependencies = [
     "Django~=5.2",
     "pillow~=12.0",
-    "django-environ>=0.12.0,<0.13",
+    "django-environ>=0.12.0,<0.14",
     "markdown~=3.9",
     "django-markup~=1.10",
     "gunicorn~=25.0",