Get Gemfile working with ruby 3.2.2

Author: thermistor

Gemfile

@@ -2,6 +2,6 @@ source 'https://rubygems.org'
 
 require 'json'
 require 'open-uri'
-versions = JSON.parse(open('https://pages.github.com/versions.json').read)
+versions = JSON.parse(::URI.open('https://pages.github.com/versions.json').read)
 
 gem 'github-pages', versions['github-pages']