Check for broken links for the deployed repository

I was wondering if there is any interest in checking for broken URLs? We're seeing some with the shell-novice lesson https://github.com/swcarpentry/shell-novice/issues/1539 and there are many existing software libraries that crawl repositories to check for broken URLs. Given that our workbench-workflows are written with R libraries, we may wish to use `httr2` to simplify the checking. There may be some advantage in looking at URLs before deployment because that would more clearly separate internal from external links. I could fork our shell-novice lesson workflow CI scripts but worry about then needing to reconcile our lesson specific CI with this upstream repository.