Is there any specific reason why we needed to change the markdown or the highlighter settings?

I was unable to get the website to generate without doing bundle update github-pages because of an error with the json dependency. Bundle updating fixed that error by updating everything in the Gemfile.lock file. The update got rid of redcarpet and pygments, so script/server wouldn't run because of missing dependencies. I googled what the alternatives were, and noticed rouge and kramdown were already in the updated Gemfile.lock. So I changed it in the config file, and script/server ran successfully, letting me generate the website.