add Python image into Matlab and R base images

[jules32]

Noting this here for us in the next corn iteration - @betolink @erinmr

Could we please add the python base image to both the Matlab and R images. Since Matlab and R will often act as wrappers or we're otherwise testing things in Python, this is a sticking point. It also came up with the NASA Mentors when the Matlab image didn't have earthaccess installed.

Also: the JupyterHub looks the same in all cases so it's confusing that python isn't there

[battistowx]

If this gets implemented, inside the Python base image, could we also include the conda package "r-irkernel" so that we can run Jupyter Notebooks with an R kernel?