Update flask-migrate requirement from <3,>=2.5.3 to >=2.5.3,<4

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@v2.5.3...v3.0.1)

---
updated-dependencies:
- dependency-name: flask-migrate
  dependency-type: direct:production
...

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

setup.cfg

@@ -30,7 +30,7 @@ install_requires =
     Flask-Babel>=1,<3
     Flask-Cors~=3.0
     Flask-Mail~=0.9
-    Flask-Migrate>=2.5.3,<3  # Not following semantic versioning (e.g. https://github.com/miguelgrinberg/flask-migrate/commit/1af28ba273de6c88544623b8dc02dd539340294b)
+    Flask-Migrate>=2.5.3,<4  # Not following semantic versioning (e.g. https://github.com/miguelgrinberg/flask-migrate/commit/1af28ba273de6c88544623b8dc02dd539340294b)
     Flask-RESTful~=0.3
     Flask-SQLAlchemy~=2.4
     Flask-WTF~=0.14,>=0.14.3  # See b76da172652da94c1f9c4b2fdd965375da8a2c3f