fix: bindings/python/sdk/batch/requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-WERKZEUG-6808933

Author: snyk-bot

bindings/python/sdk/batch/requirements.txt

@@ -1,3 +1,4 @@
 dapr>=1.13.0a,<1.14.0
 Flask
-typing-extensions
+typing-extensions
+werkzeug>=3.0.3 # not directly required, pinned by Snyk to avoid a vulnerability