Switch means of providing notebooks from stellarphot to users

[mwcraig]

We should use one of these, which allow us to provide notebooks directly from stellarphot to the jupyter lab launcher.

IIRC, either jupyterstarters or jupyter-app-launcher are the way to go.

[mwcraig]

After spending quite a while looking at these today I'm going to re-milestone to post-2.0.

Here is a summary of the current state of affairs.

• Right now notebooks are added to the launcher in a package called astronbs. It works, but is cumbersome, and I don't want to have to maintain it, ideally.
• jupyterlab-starters is almost perfect. The hangup is that the ability to group launcher items into groups is slated for 2.0.0, which has not been released yet. We could depend on the current main branch, though building is a little finicky. When this issue is closed it would be a more straightforward dependency.
• jupyter-app-launcher is also very promising. The hangup here is that there does not seem to be an easy way to specify where the notebook linked to the launcher is relative to the python package install location.

For now the only place where this is really needed is on jupyter3, so not as high a priority.

[mwcraig]

Closed by the PRs that added jupyter-app-launcher