Bump pillow in /backend in the uv group across 1 directory

Bumps the uv group with 1 update in the /backend directory: [pillow](https://github.com/python-pillow/Pillow).


Updates `pillow` from 10.4.0 to 12.2.0
- [Release notes](https://github.com/python-pillow/Pillow/releases)
- [Changelog](https://github.com/python-pillow/Pillow/blob/main/CHANGES.rst)
- [Commits](python-pillow/Pillow@10.4.0...12.2.0)

---
updated-dependencies:
- dependency-name: pillow
  dependency-version: 12.2.0
  dependency-type: direct:production
  dependency-group: uv
...

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

Author: dependabot[bot]

backend/pyproject.toml

@@ -74,7 +74,7 @@ dependencies = [
     "dal-admin-filters==1.1.0",
     "django-markdownify==0.9.5",
     "django-imagekit==5.0.0",
-    "pillow==10.4.0",
+    "pillow==12.2.0",
     "redis[hiredis]==5.0.2",
     "google-api-python-client<3.0.0,>=2.94.0",
     "google-auth<3.0.0,>=2.22.0",