Setting the base_url flag of Jupyter images (#2627)
Setting the base_url flag of Jupyter images (#2627)

* set base_url of jupyter

* change the env base_url to NB_PREFIX to sync with https://github.com/kubeflow/kubeflow/pull/2620

kubeflow/kubeflow,kubeflow/kubeflow,kubeflow/kubeflow,kubeflow/kubeflow,kubeflow/kubeflow,kubeflow/kubeflow