Adding pip install jupyterlab to docker container

[JonahRileyHuggins]

Hi all,

Certain HPC environments support containerized jupyter notebook workflows through Open OnDemand. However, I encountered the following issue when attempting to launch the container on Clemson University's Palmetto Cluster:

Traceback (most recent call last):
 File "/usr/local/bin/jupyter", line 11, in <module>
   sys.exit(main())
 File "/usr/local/lib/python3.6/dist-packages/jupyter_core/command.py", line 285, in main
   command = _jupyter_abspath(subcommand)
 File "/usr/local/lib/python3.6/dist-packages/jupyter_core/command.py", line 125, in _jupyter_abspath
   'Jupyter command `{}` not found.'.format(jupyter_subcommand): Jupyter command `jupyter-lab` not found.

The internal team working with the Palmetto Cluster suggests that we install jupyterlab via pip within this container, like so:
pip install jupyterlab

For further reference, see here.