Find a way to include setup instructions inline to lessons?

I understand the benefits of centralization and only maintaining the setup instructions in one place, but from my perspective it seems quite disorienting to link a user to [halfway down a long page](https://carpentries.github.io/workshop-template/install_instructions/#shell-windows-wsl-store) and ask them to follow the instructions in a single box and then come back. As a lesson author I would _much_ prefer to be able to include the relevant setup instructions inline without breaking flow.

Start by reviewing the linked install_instructions section and how lesson authors currently reference it. Determine a documented way to place relevant setup instructions inline without duplicating maintenance, and confirm that the resulting lesson flow keeps readers from needing to leave and return to a long page.

Written by the indexing model from the issue text.