Bump flask-migrate from 3.1.0 to 4.0.4 (#758)

Bumps [flask-migrate](https://github.com/miguelgrinberg/flask-migrate) from 3.1.0 to 4.0.4.
- [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...v4.0.4)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Willem <github@canihavesome.coffee>

Author: dependabot[bot]

requirements.txt

@@ -12,7 +12,7 @@ lxml==4.9.2
 pytz==2023.3
 tzlocal==4.1
 markdown2==2.4.8
-flask-migrate==3.1.0
+flask-migrate==4.0.4
 flask-script==2.0.6
 email_validator
 gitdb==4.0.10