Bump flask-migrate from 3.1.0 to 4.0.0

Bumps [flask-migrate](https://github.com/miguelgrinberg/flask-migrate) from 3.1.0 to 4.0.0.
- [Release notes](https://github.com/miguelgrinberg/flask-migrate/releases)
- [Changelog](https://github.com/miguelgrinberg/Flask-Migrate/blob/main/CHANGES.md)
- [Commits](miguelgrinberg/Flask-Migrate@v3.1.0...v4.0.0)

---
updated-dependencies:
- dependency-name: flask-migrate
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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