Add rendering of module cheatsheets to make-live workflow

Related to #521 and discussed this with (at?) @sjspielman in Slack.

I think we could add rendering of module cheatsheets at the same time we render/make live all of the notebooks for a training. My general approach would be to:

- Add a shell script that uses `pandoc` for the conversion (e.g., `scripts/render-cheatsheets.sh`). We _should_ be able to do this in the same container as everything else because that container needs to knit things = Pandoc should necessarily be installed.
- Add that step to make live [between rendering notebooks and before creating a pull request](https://github.com/AlexsLemonade/training-modules/blob/e480ef14ab85414d271e0d32143af41315049581/.github/workflows/make-live.yml#L42).

Read .github/workflows/make-live.yml around the notebook-rendering step and inspect the existing scripts directory. Check how Pandoc is available in the workflow container, then determine how module cheatsheets should be rendered before the pull request is created. Done means the make-live workflow renders the cheatsheets along with the training notebooks.

Written by the indexing model from the issue text.