Bump pillow from 11.3.0 to 12.1.0

Bumps [pillow](https://github.com/python-pillow/Pillow) from 11.3.0 to 12.1.0.
- [Release notes](https://github.com/python-pillow/Pillow/releases)
- [Changelog](https://github.com/python-pillow/Pillow/blob/main/CHANGES.rst)
- [Commits](python-pillow/Pillow@11.3.0...12.1.0)

---
updated-dependencies:
- dependency-name: pillow
  dependency-version: 12.1.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

requirements/base.txt

@@ -17,7 +17,7 @@ django-tree-queries==0.23.0
 jira==3.10.5
 Markdown==3.10.1
 # transient dependency of django-color-field/django-simple-captcha
-pillow==11.3.0
+pillow==12.1.0
 PyGithub==2.8.1
 Pygments==2.19.2
 python-gitlab==8.0.0