chore(deps): update flask-migrate requirement in /store/backend (#1034)

Updates the requirements on [flask-migrate](https://github.com/miguelgrinberg/flask-migrate) to permit the latest version.
- [Release notes](https://github.com/miguelgrinberg/flask-migrate/releases)
- [Changelog](https://github.com/miguelgrinberg/Flask-Migrate/blob/main/CHANGES.md)
- [Commits](miguelgrinberg/Flask-Migrate@v2.5.0...v4.1.0)

---
updated-dependencies:
- dependency-name: flask-migrate
  dependency-version: 4.1.0
  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

@@ -17,7 +17,7 @@ dependencies = [
     "flask~=2.0",
     "flask-caching~=2.0",
     "flask-shell-ipython~=0.4",
-    "flask-migrate~=2.5",
+    "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",
     "ipython~=7.19",