Update werkzeug requirement in /backend in the pip group

Updates the requirements on [werkzeug](https://github.com/pallets/werkzeug) to permit the latest version.

Updates `werkzeug` to 3.1.3
- [Release notes](https://github.com/pallets/werkzeug/releases)
- [Changelog](https://github.com/pallets/werkzeug/blob/main/CHANGES.rst)
- [Commits](pallets/werkzeug@1.0.1...3.1.3)

---
updated-dependencies:
- dependency-name: werkzeug
  dependency-type: direct:production
  dependency-group: pip
...

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

Author: dependabot[bot]

backend/pyproject.toml

@@ -69,7 +69,7 @@ dependencies = [
     "lxml<5.0.0,>=4.5.0",
     "unidecode<2.0.0,>=1.1.1",
     "strawberry-graphql==0.243.1",
-    "Werkzeug<2.0.0,>=1.0.1",
+    "Werkzeug>=1.0.1,<4.0.0",
     "django-import-export<4.0.0,>=3.2.0",
     "dal-admin-filters==1.1.0",
     "django-markdownify==0.9.5",