Update flask-limiter requirement from <3,>=2.6 to >=2.6,<4

Updates the requirements on [flask-limiter](https://github.com/alisaifee/flask-limiter) to permit the latest version.
- [Release notes](https://github.com/alisaifee/flask-limiter/releases)
- [Changelog](https://github.com/alisaifee/flask-limiter/blob/master/HISTORY.rst)
- [Commits](alisaifee/flask-limiter@2.6.0...3.9.2)

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

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

pyproject.toml

@@ -33,7 +33,7 @@ dependencies = [
     "Flask>=2,<4",
     "Flask-Babel>=1.0,<4",
     "Flask-Cors>=3.0.8,<4",
-    "Flask-Limiter>=2.6,<3",
+    "Flask-Limiter>=2.6,<4",
     "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",