[ruby/erb] Use cgi/escape instead of deprecated cgi/util

lib/erb.gemspec

@@ -33,6 +33,4 @@ Gem::Specification.new do |spec|
     spec.required_ruby_version = '>= 2.7.0'
     spec.extensions = ['ext/erb/escape/extconf.rb']
   end
-
-  spec.add_dependency 'cgi', '>= 0.3.3'
 end

lib/erb.rb

@@ -12,11 +12,7 @@
 #
 # You can redistribute it and/or modify it under the same terms as Ruby.
 
-begin
-  require 'cgi/escape'
-rescue LoadError
-  require 'cgi/util'
-end
+require 'cgi/escape'
 require 'erb/version'
 require 'erb/compiler'
 require 'erb/def_method'