fix: requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-FILELOCK-14458335

Author: snyk-bot

requirements.txt

@@ -14,3 +14,4 @@ anyconfig>=0.10.0 # not directly required, pinned by Snyk to avoid a vulnerabili
 setuptools>=65.5.1 # not directly required, pinned by Snyk to avoid a vulnerability
 urllib3>=2.5.0 # not directly required, pinned by Snyk to avoid a vulnerability
 zipp>=3.19.1 # not directly required, pinned by Snyk to avoid a vulnerability
+filelock>=3.20.1 # not directly required, pinned by Snyk to avoid a vulnerability