update JupyterBook

[aaarendt]

The current version of this hackweek's JupyterBook doesn't include some of the latest improvements we've made in the existing ICESat-2 2023 book around preliminary checklist and skills refreshers:

• link to our new ICESat-2 material

In addition, the preliminary checklist needs to be modified to align with what we'll be doing in GeoSMART. E.g.:

• is Earthdata login needed (delete)?
• add info on connecting to hub (will it be hosted by HydroShare?)
• add login info for GeoWeaver?

(adding @spestana in case this is a task you might want to jump in on!)

[jomey]

This PR to the template contains all the required commits needing transfer to here to update to the 'Preliminary' section https://github.com/uwhackweek/jupyterbook-template/pull/134