Update flask-sqlalchemy requirement from <3,>=2.4 to >=2.4,<4

Updates the requirements on [flask-sqlalchemy](https://github.com/pallets-eco/flask-sqlalchemy) to permit the latest version.
- [Release notes](https://github.com/pallets-eco/flask-sqlalchemy/releases)
- [Changelog](https://github.com/pallets-eco/flask-sqlalchemy/blob/main/CHANGES.rst)
- [Commits](pallets-eco/flask-sqlalchemy@2.4.0...3.1.1)

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

Signed-off-by: dependabot[bot] <[email protected]>

pyproject.toml

@@ -36,7 +36,7 @@ dependencies = [
     "Flask-Mail>=0.9.1,<1",
     "Flask-Migrate>=2.5.3,<5",  # Not following semantic versioning (e.g. https://github.com/miguelgrinberg/flask-migrate/commit/1af28ba273de6c88544623b8dc02dd539340294b)
     "Flask-RESTful>=0.3.9,<1",
-    "Flask-SQLAlchemy>=2.4,<3",
+    "Flask-SQLAlchemy>=2.4,<4",
     "Flask-Talisman>=0.8,<2",
     "Flask-WTF>=0.14.3,<2",
     "WTForms>=2.3.3,<3.2",