Gemfile: Switch to jekyll from Perforce

Author: bastelfreak

Gemfile

@@ -8,7 +8,8 @@ gem 'git', '~> 4.0'
 gem 'json', '~> 2.5'
 
 group(:build_site) do
-  gem 'jekyll', '~> 4.1'
+  # gem 'jekyll', '~> 4.1' # Perforce has their own legacy fork
+  gem 'jekyll', github: 'puppetlabs/jekyll', branch: 'puppetdocs'
   gem 'kramdown', '~> 2.3'
   gem 'vlad', '~> 2.7'
   gem 'vlad-git', '~> 2.1'