Commit old code before deleting it

[sstevens2]

How could the content be improved?

Suggest we show them how to commit the old code and then delete it, rather than just deleting it. So there is a record of it in our git history.

Which part of the content does your suggestion apply to?

https://carpentries-incubator.github.io/better-research-software/02-better-start-version-control.html#from-script-to-software-project