Fixed security issue with download 3rd party plugin (alshedivat#2364)

Signed-off-by: George Araujo <[email protected]>

_plugins/download-3rd-party.rb

@@ -34,7 +34,7 @@ def download_fonts(url, dest)
     unless File.directory?(dest) && !Dir.empty?(dest)
       puts "Downloading fonts from #{url} to #{dest}"
       # get available fonts from the url
-      doc = Nokogiri::HTML(URI.open(url, "User-Agent" => "Ruby/#{RUBY_VERSION}"))
+      doc = Nokogiri::HTML(URI().open(url, "User-Agent" => "Ruby/#{RUBY_VERSION}"))
       doc.css('a').each do |link|
         # get the file name from the url
         file_name = link['href'].split('/').last.split('?').first