chore(deps): update gunicorn requirement in /store/backend (#1052)

Updates the requirements on [gunicorn](https://github.com/benoitc/gunicorn) to permit the latest version.
- [Release notes](https://github.com/benoitc/gunicorn/releases)
- [Commits](benoitc/gunicorn@22.0.0...23.0.0)

---
updated-dependencies:
- dependency-name: gunicorn
  dependency-version: 23.0.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

store/backend/pyproject.toml

@@ -19,7 +19,7 @@ dependencies = [
     "flask-shell-ipython~=0.4",
     "flask-migrate~=4.1",
     "flask-sqlalchemy~=3.1", # fix multiple instance error: https://flask-sqlalchemy.palletsprojects.com/en/3.0.x/changes/#version-3-0-3
-    "gunicorn~=22.0",
+    "gunicorn~=23.0",
     "ipython~=7.19",
     "marshmallow~=3.0",
     "numpy<2.0.0",