fix: docs/requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-REQUESTS-6928867
- https://snyk.io/vuln/SNYK-PYTHON-SETUPTOOLS-3180412
- https://snyk.io/vuln/SNYK-PYTHON-URLLIB3-7267250
- https://snyk.io/vuln/SNYK-PYTHON-ZIPP-7430899

Author: snyk-bot

docs/requirements.txt

@@ -2,7 +2,7 @@ gmsh==4.11.1
 matplotlib>=3.7.3
 numpy>=1.24.4
 pybind11==2.4.3
-requests>=2.32.0 # not directly required, pinned by Snyk to avoid a vulnerability
+requests>=2.32.2 # not directly required, pinned by Snyk to avoid a vulnerability
 setuptools>=70.0.0
 sphinx==5.3.0
 sphinx-gallery==0.8.1