Bump werkzeug from 3.0.3 to 3.0.6 in /src/backend

Bumps [werkzeug](https://github.com/pallets/werkzeug) from 3.0.3 to 3.0.6.
- [Release notes](https://github.com/pallets/werkzeug/releases)
- [Changelog](https://github.com/pallets/werkzeug/blob/main/CHANGES.rst)
- [Commits](pallets/werkzeug@3.0.3...3.0.6)

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

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

Author: dependabot[bot]

src/backend/requirements.txt

@@ -17,7 +17,7 @@ s3transfer==0.6.1
 six==1.16.0
 sqlparse==0.5.0
 urllib3==1.26.19
-Werkzeug==3.0.3
+Werkzeug==3.0.6
 faiss-cpu==1.7.4
 pypdf==3.17.0
 pypdf2==3.0.1