fix: requirements/py313-django50.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-DJANGO-10074036

Author: snyk-bot

requirements/py313-django50.txt

@@ -93,7 +93,7 @@ distlib==0.3.9 \
     --hash=sha256:47f8c22fd27c27e25a65601af709b38e4f0a45ea4fc2e710f65755fa8caaaf87 \
     --hash=sha256:a60f20dea646b8a33f3e7772f74dc0b2d0772d2837ee1342a00645c81edf9403
     # via virtualenv
-django==5.0.14 \
+django==5.1.9 \
     --hash=sha256:29019a5763dbd48da1720d687c3522ef40d1c61be6fb2fad27ed79e9f655bc11 \
     --hash=sha256:e762bef8629ee704de215ebbd32062b84f4e56327eed412e5544f6f6eb1dfd74
     # via -r requirements.in