Use cgi/escape instead of deprecated cgi/util

Author: nobu

lib/rdoc/code_object/context/section.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'cgi/util'
+require 'cgi/escape'
 
 ##
 # A section of documentation like:

lib/rdoc/code_object/method_attr.rb

@@ -282,7 +282,7 @@ def block_params=(value)
   # HTML id-friendly method/attribute name
 
   def html_name
-    require 'cgi/util'
+    require 'cgi/escape'
 
     CGI.escape(@name.gsub('-', '-2D')).gsub('%', '-').sub(/^-/, '')
   end

lib/rdoc/markup/to_html.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'cgi/util'
+require 'cgi/escape'
 
 ##
 # Outputs RDoc markup as HTML.

lib/rdoc/markup/to_label.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
-require 'cgi/util'
+require 'cgi/escape'
 
 ##
 # Creates HTML-safe labels suitable for use in id attributes.  Tidylinks are