Formatting fix to list

### How could the content be improved?

The steps could be switched to be an actual list instead of a blocky paragraph

### Which part of the content does your suggestion apply to?

https://carpentries.github.io/instructor-training/checkout.html#add-your-get-involved-step-to-your-record-in-our-database-amy

Open checkout.html at the “Add your Get Involved step to your record in our database (AMY)” section and inspect the steps described there. Format the steps as an actual list rather than a blocky paragraph, then verify the rendered page shows the intended list.

Written by the indexing model from the issue text.