Comment 2 for bug 2036328

Signoff pushed to user/gmcharlt/lp2036328_signoff. It includes a follow-up that does some cleaning before installing Antora, as the 2.3 CLI from a previous build was getting used instead (and failing).

I consider that cleanup a stopgap; if we can come up with a better way so that we don't have to reinstall so much from scratch each time generate_docs.pl is used, that will save time for people who need to repeatedly build the docs.