Skip the frozen string literal comment when auto-building docs

Author: Kevin Paulisse

rake/doc.rb

@@ -24,6 +24,7 @@ def file_content(filename)
       comments = []
       IO.readlines(filename).each do |line|
         next if line =~ /^#\s*@/
+        next if line.strip == '# frozen_string_literal: true'
         if line =~ /^#(.+)/
           comments << Regexp.last_match(1).strip
         elsif line =~ /^OctocatalogDiff::/