Bump gunicorn from 25.1.0 to 25.3.0

Bumps [gunicorn](https://github.com/benoitc/gunicorn) from 25.1.0 to 25.3.0.
- [Release notes](https://github.com/benoitc/gunicorn/releases)
- [Commits](benoitc/gunicorn@25.1.0...25.3.0)

---
updated-dependencies:
- dependency-name: gunicorn
  dependency-version: 25.3.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements.txt

@@ -1,7 +1,7 @@
 Flask==3.1.3
 Flask-SQLAlchemy==3.1.1
 Flask-Login==0.6.3
-gunicorn==25.1.0
+gunicorn==25.3.0
 Werkzeug==3.1.6
 pyotp==2.9.0
 qrcode==8.2