Removed vendored resolv

Manifest.txt

@@ -576,8 +576,6 @@ lib/rubygems/vendor/optparse/lib/optparse/shellwords.rb
 lib/rubygems/vendor/optparse/lib/optparse/time.rb
 lib/rubygems/vendor/optparse/lib/optparse/uri.rb
 lib/rubygems/vendor/optparse/lib/optparse/version.rb
-lib/rubygems/vendor/resolv/COPYING
-lib/rubygems/vendor/resolv/lib/resolv.rb
 lib/rubygems/vendor/securerandom/COPYING
 lib/rubygems/vendor/securerandom/lib/securerandom.rb
 lib/rubygems/vendor/timeout/COPYING

lib/rubygems/vendor/net-http/lib/net/http.rb

@@ -22,7 +22,7 @@
 
 require_relative '../../../net-protocol/lib/net/protocol'
 require_relative '../../../uri/lib/uri'
-require_relative '../../../resolv/lib/resolv'
+require 'resolv'
 autoload :OpenSSL, 'openssl'
 
 module Gem::Net   #:nodoc:
@@ -1734,7 +1734,7 @@ def connect
 
         # Server Name Indication (SNI) RFC 3546/6066
         case @address
-        when Gem::Resolv::IPv4::Regex, Gem::Resolv::IPv6::Regex
+        when Resolv::IPv4::Regex, Resolv::IPv6::Regex
           # don't set SNI, as IP addresses in SNI is not valid
           # per RFC 6066, section 3.