fix: sdk/python/kubeflow/trainer/requirements.txt to reduce vulnerabilities

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

Author: snyk-bot

sdk/python/kubeflow/trainer/requirements.txt

@@ -1,3 +1,4 @@
 peft==0.3.0
 datasets==2.15.0
 transformers==4.37.2
+setuptools>=70.0.0 # not directly required, pinned by Snyk to avoid a vulnerability