[jupyterhub] move ipython dir out of ~

jupyterhub/base/Dockerfile

@@ -21,6 +21,7 @@ RUN curl -sL https://deb.nodesource.com/setup_10.x | bash - && \
     npm config set cache /var/cache/npm --global && \
     npm config set update-notifier false --global
 
+ENV IPYTHONDIR=/usr/local/etc/ipython
 COPY jupyter_notebook_config.py /usr/local/etc/jupyter
 ENV JUPYTER_CONFIG_DIR=/usr/local/etc/jupyter/jupyter
 ENV JUPYTERLAB_SETTINGS_DIR=/root/.config/jupyter/lab/user-settings