fix: requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-PILLOW-6219984
- https://snyk.io/vuln/SNYK-PYTHON-PILLOW-6219986

requirements.txt

@@ -6,4 +6,4 @@ sectionproperties >= 2.1.3
 meshio
 triangle
 numpy>=1.22.2 # not directly required, pinned by Snyk to avoid a vulnerability
-pillow>=10.0.1 # not directly required, pinned by Snyk to avoid a vulnerability
+pillow>=10.2.0 # not directly required, pinned by Snyk to avoid a vulnerability