Fix the link to run_e2e_workflow.py script

Author: terrytangyuan

prow_config.yaml

@@ -1,5 +1,5 @@
 # This file configures the workflows to trigger in our Prow jobs.
-# see kubeflow/testing/py/run_e2e_workflow.py
+# see https://github.com/kubeflow/testing/blob/master/py/kubeflow/testing/run_e2e_workflow.py
 workflows:
   - app_dir: kubeflow/pytorch-operator/test/workflows
     component: workflows