fix: requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-SETUPTOOLS-9964606

Author: snyk-bot

requirements.txt

@@ -23,5 +23,5 @@ whoosh
 wsgi-intercept
 xmldiff
 str2bool
-setuptools>=70.0.0 # not directly required, pinned by Snyk to avoid a vulnerability
+setuptools>=78.1.1 # not directly required, pinned by Snyk to avoid a vulnerability
 zipp>=3.19.1 # not directly required, pinned by Snyk to avoid a vulnerability