fix: requirements/requirements_docs.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-SETUPTOOLS-7448482

requirements/requirements_docs.txt

@@ -1,6 +1,6 @@
 apppath
 #mistune==0.8.4 #>=2.0.1 # not directly required, pinned by Snyk to avoid a vulnerability
-setuptools>=65.5.1 # not directly required, pinned by Snyk to avoid a vulnerability
+setuptools>=70.0.0 # not directly required, pinned by Snyk to avoid a vulnerability
 sphinx
 #m2r2>=0.2.0
 sphinxcontrib-programoutput